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Riis et al.: Bionomics of Cyrtomenus bergi on host plants


BIONOMICS AND POPULATION GROWTH STATISTICS OF CYRTOMENUS
BERGI (HEMIPTERA: CYDNIDAE) ON DIFFERENT HOST PLANTS


LISBETH RIIS'2, ANTHONY CHARLES BELLOTTI1 AND BERNARDO ARIAS1
1Centro International de Agricultural Tropical (CIAT), Pest and Disease Management Unit
A.A. 6713 Cali, Colombia S.A.

2Department of Ecology and Molecular Biology, Royal Veterinary and Agricultural University (RVAU)
Copenhagen, Denmark

ABSTRACT

Cyrtomenus bergi Froeschner (Hemiptera: Cydnidae) is a polyphagous subterranean bur-
rower bug reported on various crops and weeds in the field. Bionomics and population
growth statistics of C. bergi while feeding on peanut (Arachis hypogaea L.), pinto peanut
(Arachis pintoi, Krapovickas et Gregory), maize (Zea mays L.), sorghum (Sorghum bicolor
[L.] Moench), welsh onion (Allium fistulosum L.),and sweet and bitter cassava (Manihot es-
culenta Crantz) were calculated from development time, survival of immature stages, and
reproduction and female longevity under laboratory conditions. Free-choice host plant selec-
tion among peanut, maize and sweet cassava was recorded with separate hearings of C. bergi
from the different hosts. Optimal performance of C. bergi as measured by fecundity, sur-
vival, and intrinsic rate of population increase occurred on peanut and pinto peanut followed
by maize. Sweet cassava, sorghum, and welsh onion were not favorable hosts, and C. bergi
was unable to complete its life cycle on bitter cassava. In the free-choice test, insects reared
on peanut and maize prior to the experiments were less active in their search for food,
whereas insects reared on cassava prior to the experiment showed a clear preference for pea-
nut and maize over cassava. Our results show that C. bergi is highly polyphagous, however,
some host plants are strongly preferred over others. Cassava is not a preferred host and
weeds in and around the cassava field may serve as alternative host plants that could main-
tain populations of C. bergi in cassava.

Key Words: Soil pest, cassava, maize, peanut, welsh onion, sorghum, Cyrtomenus bergi,
Hemiptera

RESUME

Cyrtomenus bergi Froeschner (Hemiptera: Cydnidae) es un insecto barrenador subterraneo
polifago que ha sido reportado en diversos cultivos y malezas en el campo. La bionomia y las
estadisticas de crecimiento poblacional de C. bergi, mientras se alimentaba de mani (Arachis
hypogaea L.), mani forrajero (Arachis pintoi, Krapovickas et Gregory), maiz (Zea mays L.),
sorgo (Sorghum bicolor [L.] Moench), cebolleta (Allium fistulosum L.), yuca dulce y amarga
(Manihot esculenta Crantz), se calcularon a partir de los datos sobre duraci6n del desarrollo
y supervivencia de las etapas inmaduras, reproducci6n y longevidad de las hembras en
condiciones de laboratorio. Se registry la selecci6n de plants hospedantes en un ensayo de
libre eleccin entire el mani, el maiz y la yuca dulce, empleando crias separadas de C. bergi de
los diferentes hospedantes. Con base en los resultados de fecundidad, la supervivencia y la
tasa intrinseca del aumento de poblaci6n, el comportamiento 6ptimo de C. bergi se present
en mani y en mani forrajero, seguido del maiz. La yuca dulce, el sorgo y la cebolleta no re-
sultaron ser hospedantes favorables y C. bergi no pudo completar su ciclo de vida en la yuca
amarga, En el ensayo de libre elecci6n, los insects criados en el mani y el maiz antes de los
experiments resultaron ser menos activos en la busqueda de alimento, mientras que los in-
sectos criados en la yuca antes del experiment mostraron una clara preferencia por el mani
y el maiz respect a la yuca. Los resultados indican que C. bergi es altamente polifago; sin
embargo, este insecto muestra mayor preferencia por algunas plants hospedantes que por
otras. La yuca no muestra ser una plant hospedante preferida y malezas dentro y alrededor
del cultivo de yucca pueda servir como plant hospedante alternative manteniendo la po-
blaci6n de C. bergi en la yuca.

Translation provided by the authors.


The subterranean burrower bug Cyrtomenus sava (Manihot esculenta Crantz), maize (Zea
bergi Froeschner (Hemiptera: Cydnidae) is a Mays L.), peanut (Arachis hypogaea L.), potato
polyphageous pest, reported in crops such as cas- (Solanum tuberosum L.), onion (Allium cepa L.),







Florida Entomologist 88(1)


welsh onion (Allium fistulosum L.), sorghum
(Sorghum bicolor [L.] Moench), African oil palm
(Elaeis guineesis Jacq.), coffee (Coffea arabica L.),
sugarcane (Saccharum officinarum L.), beans
(Phaseolus vulgaris L.), peas (Pisum sativum L.),
coriander (Coriandrum sativum L.), pastures and
weeds (CIAT 1989, Cividanes et al. 1981, Lacerda
1983, Herrera 1988), and recently reported in as-
paragus (Asparagus officinalis L.) (Bellotti un-
published). C. bergi was first reported in welsh
onion in 1974 (Higuita 1974, cited by Herrera
1988) and thereafter in maize (ICA 1980) and cas-
sava (CIAT 1980). Since then, it has become a se-
rious pest problem in regions throughout the neo-
tropics (Bellotti et al. 1988).
All immature stages and the imago of C. bergi
live in the soil. Oviposition also takes place there.
Both adults and nymphs feed on roots, tubers and
subterranean fruits (e.g., peanut) of the host
plants leaving lesions in the plant tissue that fa-
cilitate the entrance of soil pathogens such as
Fusarium,Aspergillus, Genicularia, and Phytium
(CIAT 1980). On cassava, the infections appear as
delimited dry rot spots (approx. 5 mm diameter)
on the interior white starchy and edible paren-
chyma. Tissue degradation appears 12 to 24 h af-
ter feeding is initiated and is detectable when the
root is peeled (Garcia 1982). In cassava up to 85%
of root damage (CIAT 1983) and up to 51% of
starch reduction (CIAT 1985) can be ascribed to
C. bergi. In maize, reddish spots appear at the
feeding site and root rot and leaf chlorosis have
been observed. A severe attack during early crop
stages can cause wilting (King & Saunders 1984).
In peanut both nymphs and adults pierce the
pods and feed on the kernels. A light attack will
cause delimited yellow to brownish dry rot spots
(approx. 1.5 mm diameter) on the kernels of both
mature and immature pods (Riis unpublished)
and a severe attack can cause a complete decom-
position of the harvest. Similar symptoms in pea-
nut have been observed in Texas, USA, with the
closely related Cydnidae, Pangaeus bilineatus
Say (Smith & Pitts 1971).
It has not been possible to quantify damage
due to C. bergi in the field in any of the reported
crops apart from cassava where damage is as-
sessed as a percentage of the parenchyma surface
covered by rot spots. From a linear regression be-
tween percentage of cassava roots damaged and
the number of C. bergi simultaneously collected
at the same site during four crop cycles, Riis
(1990) found 22% roots damaged when the num-
ber of C. bergi was close to zero (intercept, 22%),
and the economic injury threshold was found to
be 20-30% roots damaged (Bellotti et al. 1988).
An examination of life table parameters was
conducted to obtain information on quality of a
number of host plants. Experiments compare lab-
oratory results on the development, survival, re-
production, and estimated life table parameters


for C. bergi while feeding on several host plants.
Free-choice host selection tests for ovipositing fe-
males were conducted on females with different
host plant experience.

MATERIALS AND METHODS
Stock Colonies

Cyrtomenus bergi was taken from stock labo-
ratory colonies (23 + 2C, r.h. 65 + 5%, L12:D12)
maintained on sprouting maize and peanut, re-
spectively, in unsterilized soil (loamy clay) kept at
a moisture level approximated to the field capac-
ity (33.5% gravimetric soil water).

Experimental Host Plants

Fecundity, survival, and development were as-
sessed on the following host plant diets: Sprout-
ing peanut (Arachis hypogaea L. cv. Tatui SM-76),
pinto peanut (also called wild peanut, Arachis
pintoi, Krapovickas et Gregory cv. Amarillo),
maize (Zea mays L. cv. ICA V-156), and sorghum
(Sorghum bicolor (L.) Moench cv. HW1758), root
discs of a sweet cassava variety (Manihot escu-
lenta Crantz cv. MCOL1468, < 100 ppm hydrogen
cyanide measured), a bitter cassava variety
(Manihot esculenta, Crantz cv. MCOL1684, >100
ppm hydrogen cyanide measured), and subterra-
nean culms with primary roots of welsh onion (Al-
lium fistulosum L.). Sprouting peanut, maize, and
sorghum were placed in humid germination
chambers 4 d before use. Cassava was harvested
at the age of 7-12 months and chopped into 1 cm
thick root discs. Welsh onions were bought from
the local vegetable market and 3-cm culm, includ-
ing primary roots, was provided to the insects.

Development Time and Survival of Immature Stages

Development time and survival of the five im-
mature stages of C. bergi were assessed in a tem-
perature and light controlled room (25 1.5C,
r.h. 65 + 5%, L12:D12). To determine the nymphal
development from hatching of eggs to adult, re-
cently emerged (<16 h) first instars from the
'maize colony' were placed individually in approx-
imately 30 cm3 soil (loamy clay, approx. 33% soil
water content) in opaque plastic vials (55 cm3).
One hundred individuals were placed on each
host plant diet. Every 2 d the plant diet was re-
newed and the soil of each plastic vial was
searched for exuviae until all nymphs had molted
to the adult stage. Mortality of each instar and
the number of days required to complete each life
stage were recorded. Since observations were
made every 2 d, subtracting 0.5 d approximated
the development time of each life stage. An anal-
ysis of variance and subsequent REGWQ group-
ing (SAS Institute 1988) was computed for the


March 2005







Riis et al.: Bionomics of Cyrtomenus bergi on host plants


development time of each instar to facilitate com-
parisons among host plant diets.

Reproduction and Female Longevity

Fecundity and post-teneral female longevity
were assessed for each experimental host plant
diet (25 1.5C, r.h. 65 + 5%, L12:D12) with co-
horts of 25-30 adult females recovered at ecdysis
(<16 h after) from the 'maize colony'. This was re-
peated on the experimental peanut diet with in-
sects from the 'peanut colony'. Each couple (19:
16) was placed separately in approx. 50 cm3 soil
(loamy clay, approx. 33% soil water content) in
opaque plastic vials (55 cm3). Female survival was
assessed every 2 d and the food diet was replaced
at the same time. Dead males were replaced with
males from stock colonies. Fecundity was assessed
every 2 weeks. After transferring each couple into
a new plastic vial with new soil, each old soil sam-
ple, representing oviposition of two weeks, was
separately poured into 20% salt solution and the
eggs floated off for recovery and counting (Matte-
son 1966). Egg fertility (% eggs hatched) and pre-
eclosion period were recorded from random sam-
ples of 50 eggs (four replications; total of 200 eggs)
deposited by approx. 25 females at the age of 30-
100 d after adult emergence when feeding on each
of the host plant diets.

Statistics

From the survivorship and fertility schedules,
the following bionomical statistics were calculated
(Birch 1948; Carey 1993; Hulting et al. 1990).
Net reproductive rate (R,):

Ro = lx i (1)
x=O

is the average number of newborn offspring pro-
duced by an average female during one genera-
tion calculated as the sum of realized fecundity of
all age x, where 1 denotes the fraction of surviv-
ing females at age x and m denotes the age-spe-
cific birth rate.
Intrinsic rate of increase (rm):

Nt = No. e (2)

is the instantaneous rate of change of population
size of an exponentially growing population ex-
pressed in numbers per unit time (day1) per indi-
vidual. We approximated r, by the iterative
method to the solution of the Lotka equation
(Hulting et al. 1990):


e xlxmx = 1 (3)
x =


Finite rate of increase (X):


N, = No '


is the rate at which the population increases (geo-
metrically) per individual per unit time (day1), i.e.,


= em


Generation time (T) (days):


r .
Ro = 1 e


is the average maternal age at which offspring
are born. For an exponentially growing popula-
tion of iterative offspring producers the genera-
tion time (T) can be calculated from the equation
of exponential populations growth (Equation 2)
by setting the initial population size to one female
(N0 = 1). After one generation (T), the population
size is equal to the net reproductive rate (N, = R,),
see equations 6 and 7.
Population doubling time (D) (days):


Nt = No 2


t = 2 = (e m)t or (em)D = 2


D = ln2/rm


is the time required for the population to double
which can be calculated from the equation of geo-
metric increase (equation 4) when = 2, see equa-
tions 8, 9 and 10.
Data on development time and survival of im-
mature stages were included in the above calcula-
tions. Calculations were based on a sex-ratio of
1:1, which has been found in fields of both peanut
and welsh onion from determining the sex of a to-
tal of 1833 adult individuals at three localities
(Riis unpublished). Calculations were also based
on the assumption that the egg fertility of eggs
deposited throughout the post-teneral female life
span was constant.
An analysis of variance and subsequent
REGWQ grouping (SAS Institute 1988) was ac-
complished for the post-teneral female longevity
and the area under the my-curve (fecundity
weighted by age) to facilitate comparisons among







Florida Entomologist 88(1)


host plant diets. Heterogeneity of error was ad-
dressed by transforming the data of female lon-
gevity, days"0, and fecundity, ln(area+l), and the
null hypothesis Ho: b = 0 for Taylor's Power Law,
s2 = a + Vb, was accepted for the transformed data.

Host Plant Selection

A free-choice host plant selection design was
set up with ovipositing females from different
host plant experience, i.e., reared on peanut,
maize, and cassava, respectively, for one genera-
tion. Specially made triangular wood boxes (60
cm side length; 6 cm height) were filled with
moist soil (33% soil water). A triangle consists of
four sub-triangles and each sub-triangle at each
corner was filled with sprouting kernels of either
peanut, maize, or root discs of a sweet cassava va-
riety 'MCOL1468', respectively (Fig. 1). Three tri-
angular boxes were set up simultaneously. One
hundred females from each of the three rearing
colonies were placed in the center of the triangle-
sub-triangle, which did not contain a host plant
(Fig. 1). The distribution of females and ovipos-
ited eggs were assessed after 24 h by calculating
the number of females recovered in each sub-tri-
angle. Soil from each sub-triangle was separately
poured in a 20% salt solution and the eggs floated
off for recovery and counting (Matteson 1966).
The setup was repeated seven times with new fe-
males each time.

RESULTS

Development Time and Survival of Immature Stages

Cyrtomenus. bergi can develop on a wide range
of host plants (Table 1). The nymphal develop-
ment time, however, differed significantly among
hosts (P < 0.0001) (Table 1), and ranking accord-
ing to shortest development time was peanut,
pinto peanut << maize, sweet cassava, sorghum
<< welsh onion << bitter cassava. This ranking
was consistent for each of the individual nymphal






100 females


Fig. 1. Free-choice host selection design.


stages, with exception of first and fifth instars.
The development time of first instars did not differ
significantly between the pinto peanut and sweet
cassava hosts, neither did it differ significantly
among maize, sorghum, welsh onion, and bitter
cassava. The development time of the fifth instars
did not differ significantly between the peanut
and maize. The development time per instar in-
creased significantly as the nymphs developed (F
= 290.8, df= 946, P < 0.0001), however, second and
third instar nymphs feeding on the peanut had
shorter duration than first instars. The develop-
ment time of fifth instars occupied 29-39% of the
total nymphal development time. Cyrtomenus
bergi was unable to complete its nymphal develop-
ment on the bitter cassava variety MCOL1684.
Ranking according to nymphal survival was
peanut, pinto peanut >> maize >> welsh onion >
sweet cassava, sorghum >>bitter cassava. Almost
complete survival occurred for nymphs feeding on
peanut (98%), whereas all nymphs feeding on bit-
ter cassava died prior to the fifth instar. In gen-
eral, mortality was highest in the first instar and
decreased with development. Relatively high
mortality occurred during the fifth instar for
nymphs feeding on sweet cassava (8%) and dur-
ing the third instar on sorghum (9%) (Table 1).

Female Longevity

Survivals of post-teneral females are illus-
trated in Fig. 2. Longevity while feeding on the
different host plants differed significantly (P <
0.0001) (Table 2), and ranking according to in-
creasing longevity was peanut, pinto peanut >
sweet cassava > maize >> bitter cassava.

Reproduction

Eggs are deposited singly in the soil. Age-spe-
cific fecundity is illustrated in Fig. 3. Total fecun-
dity per female differed significantly among host
plants (P < 0.0001) (Table 2), and ranking accord-
ing to increasing progeny per female was peanut,
pinto peanut > maize > sweet cassava >> bitter
cassava. Females reared on peanut prior to the
experiment and subsequently feeding on peanut
and pinto peanut showed major ovipositional
peaks at 70 and 100 d after adult emergence, re-
spectively. Additional peaks were observed three
to four times during the female life span (Fig. 3a).
Females reared on maize prior to the experiment
and subsequently feeding on peanut showed a
major ovipositional peak slightly later at approx.
125 d after adult emergence and only two addi-
tional ovipositional peaks during the female life
span at approx. 250 and 335 d after adult emer-
gence (Fig. 3b). Females reared on maize prior to
the experiment and subsequently feeding on
maize or sweet cassava also showed a major ovi-
positional peak at approx. 125 d after adult emer-


March 2005




















TABLE 1. DEVELOPMENT TIME (DAYS) AND MORTALITY (%) OF INSTARS OF CYRTOMENUS BERGI (N, = 100) WHILE FEEDING ON DIFFERENT HOST PLANTS.

Total of all
1" 2nd 3'd 4th 5th immature stages
Feeding Experimental
history' host plant Days2 % Days % Days % Days % Days % Days %

Maize Peanut 9.9 + 0.13 a3 0 7.6 + 0.17 a 0 9.3 + 0.16 a 0 10.8 0.20 a 0 24.6 0.26 a 2 62.4 0.48 a 2
Maize Pinto peanut 11.0 0.34 ab 0 10.1+ 0.35 a 0 9.3 0.28 a 2 12.0 0.31 a 0 23.0 + 0.31 a 0 65.3 0.47 a 2
Maize Maize 14.6 0.26 c 25 15.6 0.24 b 7 16.6 0.27 b 7 18.2 0.23 b 2 26.5 0.40 ab 3 91.5 0.58 b 38
Maize Sweet cassava 12.0 0.49 b 54 14.4 0.82 b 0 17.2 1.08 b 4 19.1 1.30 b 0 28.6 0.94 b 18 91.3 2.83 b 64
Maize Sorghum 14.0 0.29 c 41 14.6 0.40 b 2 16.0 0.55 b 16 19.2 0.46 b 2 27.5 0.53 b 4 91.8 + 1.14 b 64
Maize Welsh onion 15.4 0.36 c 34 19.2 0.47 c 17 23.6 0.47 c 11 24.5 0.63 c 4 36.6 0.74 c 6 119.3 0.99 c 56
Maize Bitter cassava 15.5 1.35 c 83 26.7 4.63 d 47 40.0 3.00 d 78 100 100
ANOVA4 df = 302 df = 267 df= 239 df = 234 df =222 df= 18
F = 32.31**** F = 73.15**** F = 148.3**** F = 108.6**** F = 80.73**** F = 235.9****

Feeding history prior to the experiment.
Values are means standard errors. A single-classification analysis of variance was applied separately to each instar.
REGWQ-grouping: Means with the same letter within the same column are not significantly different.
'**** denotes P < 0.0001.







Florida Entomologist 88(1)


Peanut [ Pinto peanut
/ Peanut o
Peanut A
Maize Sweet cassava
Maize *
Bitter cassava


Age (days)

Fig. 2. Fractional age-specific survival of Cyrtomenus bergi females while feeding on different host plants (25C),
and after having been reared on peanut and maize, respectively, prior to the experiment.


gence, but oviposition remained high until
approx. 200 d after adult emergence before ovipo-
sition eventually declined (Fig. 3b).
The ovipositional midpoint (50%) occurred at
approx. 130 d after adult emergence while feeding
on the peanut and maize, and at approximately
150 d after adult emergence while feeding on the


sweet and bitter cassava (Table 2), but the differ-
ence was not significant (P < 0.7339) (Table 2).
Nevertheless, when these values were calculated
as a percentage of adult female life span, a signif-
icant difference among host plants was observed
(P < 0.0001) (Table 2). Females deposited 50% of
their eggs in the first 40-45% of their adult life


TABLE 2. FEMALES LONGEVITY, TOTAL FECUNDITY PER FEMALES, PERCENT OVIPOSITING FEMALES, OVIPOSITIONAL MID-
POINT (50%), AND OVIPOSITIONAL MIDPOINT AS A PERCENTAGE OF ADULT FEMALE LIFESPAN OF CYRTOMENUS
BERGI WHILE FEEDING ON DIFFERENT HOST PLANTS.

Ovipositional
midpoint as a
Female Total fecundity Ovipositional percentage of
Feeding Experimental longevity per female Ovipositing midpoint adult female
history' host plant n2 (days)34 (eggs)3'5 females (50%) (days)' lifespan'

Peanut Peanut 25 316.1 19.9 a6 224.1 24.1 a 100% 127.4 11.5 a 39.7% 2.0 a
Peanut Pinto peanut 25 310.9 20.6 a 252.4 31.7 a 100% 133.7 12.0 a 45.1% 3.4 a
Maize Peanut 30 270.3 15.0 ab 164.0 20.7 ab 97% 136.2 8.9 a 50.3% 1.8 ab
Maize Maize 28 199.1 13.6 c 93.0 13.4 bc 93% 131.1+ 9.3 a 64.6% 3.1 ab
Maize Sweet cassava 26 232.2 16.5 bc 52.3 9.5 c 88% 150.3 9.9 a 62.5% 3.9 ab
Maize Bitter cassava 25 111.7 11.0 d 1.3 1.3 d 4% 153.0 0.0 a 70.8% 0.0 b
Maize Sorghum -
Maize Welsh onion
ANOVA7 df =153 df= 153 df= 123 df= 123
F = 21.37**** F = 67.31**** F = 0.56 NS F = 11.47****

'Feeding history prior to the experiment.
'n denotes sample size.
'Values are means + standard errors.
'Single-classification analysis of variance was run on the number of days of longevity transformed as days0 ;
"Single-classification analysis of variance was run on the area under the mn-curves transformed as In(area+l);
'REGWQ-grouping: Means with the same letter within the same column are not significantly different.
'**** denotes P< 0.0001; NS denotes not significant.


1.0 -
0.9 -
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1 -
0.0 -


March 2005


, T 03 >,r rb r,>







Riis et al.: Bionomics of Cyrtomenus bergi on host plants


Peanut- EPinto peanut
PeanuPeanut


27.5
25.0
22.5
20.0
17.5
15.0
12.5
10.0
7.5
5.0
2.5
0.0





15.0

12.5

10.0

7.5

5.0

2.5

0.0


S I I I I I
O'b '^ p Q?>?
-P0 1 *- `3


Age (days)
Fig. 3. Age-specific fecundity of Cyrtomenus bergi while feeding on different host plants (25 C), and after having
been reared on peanut (a) and maize (b), respectively, prior to the experiment.


span when feeding on the peanut both before and
during the experiment. When reared on maize
prior to the experiment, females deposited 50% of
their eggs within the first 50-65% of their life
span while feeding on peanut, maize, and sweet
cassava and within the first 70% of their life span
while feeding on bitter cassava.
The pre-oviposition period ranged between 14-
28 d on all hosts with exception of the bitter cas-
sava, where only one female deposited eggs after
84 pre-ovipositional days (Table 3). Mean egg fer-
tility was 90.5% and mean egg eclosion time was
13.5 d. Neither egg eclosion time nor mean egg
fertility differed significantly among the host
plants.


Population Growth Statistics

All life-table parameters with exception of egg
fertility and eclosion time were found to be depen-
dant on the host plant (Table 3). Net reproductive
rate (R,) was greatest for pinto peanut followed by
peanut, and declined considerably for maize and
sweet cassava. The intrinsic rate of increase (rm)
was significantly higher for females feeding on
peanut, after pre-experimental rearing on peanut
(Table 3) than after pre-experimental rearing on
maize. For females reared on maize, the ranking
according to increasing rm-value was peanut >>
maize >> sweet cassava. The values of doubling
time (D) and mean generation time (T) decreased


I 4' 1


Q, 1b 43 lz N b Ib W ^^ b^







Florida Entomologist 88(1)


March 2005


TABLE 3. DEMOGRAPHIC PARAMETERS FOR CYRTOMENUS BERGI FEEDING ON DIFFERENT HOST PLANTS AT 25C.

Mean
Net Finite rate Doubling generation
Feeding Experimental reproductive Intrinsic rate of of increase time (D) time (T)
history' host plant n2 rate (R)3 increase (rm)/day4 (,)/day (days)5 (days)5

Peanut Peanut 25 98.8 10.6 0.0318 0.0009 a6 1.0323 22.0 145
Peanut Pinto peanut 25 111.2 14.0 0.0290 0.0011 a 1.0294 23.8 162
Maize Peanut 30 72.3 9.2 0.0250 0.0009 b 1.0254 27.6 170
Maize Maize 28 25.9 4.6 0.0154 0.0015 c 1.0155 44.8 210
Maize Sweet cassava 26 8.5 1.5 0.0087 0.0009 d 1.0088 77.7 240
Maize Bitter cassava 25 -
Maize Sorghum -
Maize Welsh onion

1Feeding history prior to the experiment.
2n denotes sample size.
Values of the net reproductive rate are means + standard errors.
'Values of the intrinsic rate of increase are based on estimates of r + standard error of Jackknife estimates (Carey 1993).
5Values of the finite rate of increase, doubling time and mean generation time are means.
'Means that lie within the 95% confidence interval of other means have the same letter.


as the intrinsic rate of increase (rm) increased
(Table 3).

Host Selection

Within a time frame of 24 h, higher numbers of
ovipositing females, which were reared on peanut
(P < 0.0001) and maize (P < 0.0018), remained at
the release point, where no host plant was avail-
able, rather than moving to spaces with hosts (Ta-
ble 4). On the contrary, females reared on sweet
cassava preferred peanut and maize over sweet
cassava (P < 0.0001), and proportionally more fe-
males moved towards the two preferred hosts


rather than staying at the release point with no
host plants available (Table 4).
The distribution of oviposited eggs within the
experimental space corresponded with the distri-
bution of the females. Oviposition of females
reared on peanut was high. Oviposition of females
reared on maize and sweet cassava was low and
there were no differences among hosts (Table 4).

DISCUSSION

Our results confirm that C. bergi is highly
polyphagous. It can develop on a range of host
plants from different families, but some host


TABLE 4. HOST PLANTS SELECTED BY 15-30 D OLD OVIPOSITING FEMALES OF CYRTOMENUS BERGI (N = 100) 24 H AFTER
RELEASE IN A HOST PLANT FREE SPACE (SEE FIG. 1). THE SPECIMENS WERE TAKEN FROM THREE DIFFERENT
COLONIES IN WHICH THEY FED ON PEANUT, MAIZE, AND SWEET CASSAVA, RESPECTIVELY, FOR ONE GENERA-
TION PRIOR TO THE EXPERIMENT.

Pre-experimental colony

Host plant Peanut Maize Sweet cassava
selected
by C. bergi: Females Eggs Females Eggs Females Eggs

Release point' 56.5 10.1 a3 39.0 9.3 a 50.3 11.2 a 24.0 + 9.1 a 20.7 4.0 ab 18.8 6.4 a
(no host plant)
Peanut2 17.9 5.0 b 10.2 + 3.8 b 21.3 5.7 b 8.7 5.3 a 33.4 + 2.1 a 7.2 2.8 a
Maize2 16.1 + 4.2 b 8.0 2.1 b 18.3 4.4 b 7.8 3.7 a 32.6 2.0 a 10.7 3.8 a
Sweet cassava2 9.3 2.2 b 10.7 3.5 b 9.9 2.1 b 10.7 3.6 a 13.1 3.1 b 9.8 3.7 a
ANOVA4 df = 24 df =24 df= 24 df =24 df= 24 df = 24
F = 12.18**** F= 10.38**** F = 6.77** F = 2.31 NS F= 11.21**** F= 1.85 NS

Values are means of numbers of females located within each space standard errors;
Single-classification analyses of variance were applied separately to each group of host plant regime before test;
Insects were released in the central 'sub-triangle-space' of a triangle;
The 'sub-triangle-space' of one corner in a triangle;
'REGWQ-grouping: Means with the same letter within the same column are not significantly different.
'**** denotes P < 0.0001; ** denotes P < 0.001; NS, not significant.







Riis et al.: Bionomics of Cyrtomenus bergi on host plants


plants are strongly preferred over others. Best
performance of C. bergi measured as fecundity,
survival, and intrinsic rate of population increase,
occurred on peanut and pinto peanut followed by
maize. Sweet cassava, sorghum, and welsh onion
were not favorable hosts, and C. bergi was unable
to complete its life cycle on bitter cassava. The
computation of the intrinsic rate of increase (rm)
(day-1) resulted in a clear differentiation of the
host plant qualities, and also the impact of the
feeding history prior to the experiment was highly
significant. The intrinsic rate of increase was sig-
nificantly higher for insects feeding on peanut af-
ter pre-experimental rearing on peanut than after
pre-experimental rearing on maize. The develop-
ment time of nymphs feeding on sweet cassava af-
ter pre-experimental rearing on maize was 91.3 d
compared with 111.3 d after pre-experimental
rearing on sweet cassava (Garcia 1982).
Nymphal development was consistently com-
pleted with five instars. In general, the develop-
ment time increased as the instars increased,
however, on peanut the second and third instars
developed faster than the first instars indicating
a major plasticity of these intermediate instars.
Although the development time on maize was
not significantly different from that on sweet cas-
sava and sorghum, maize offered better host
qualities than sweet cassava and sorghum due to
higher survival; 62% on maize compared with
36% on sweet cassava and sorghum. In the field,
Peairs and Carballo (1987) found higher numbers
of C. bergi in maize as a monoculture and in a
maize-cassava intercropping than in cassava mo-
noculture. Unfortunately, they did not assess the
damage caused by C. bergi to explain whether
maize acts as a trap crop reducing damage to cas-
sava intercropped with maize, or alternatively,
whether the damage to cassava in the intercrop-
ping system increases due to increased popula-
tion density of C. bergi.
The total average life spans (egg eclosion time
+ nymphal development time + female longevity)
for C. bergi feeding on the two types of peanut
were 360-380 d. Interestingly, the total average
life span for insects feeding on maize was only 290
d compared with 324 d for insects feeding on
sweet cassava after pre-experimental rearing on
maize in spite of the reproduction being higher on
maize than on sweet cassava. Reduced reproduc-
tion and increased longevity while feeding on cas-
sava compared with maize demonstrates a
possible physiological trade-off between reproduc-
tion and longevity consistent with the 'principle of
allocation' paradigm (Pianka 1988). The increase
in life span caused by dietary restriction can be
explained as a consequence of lower reproduction.
This response may enable C. bergi to adapt in-
creased fitness when encountering favorable food
supply. Garcia (1982) found that C. bergi had a
greater total average life span of 418 d when feed-


ing on root discs of sweet cassava after pre-exper-
imental rearing on cassava. However, Garcia
(1982) did not collect data on fecundity from the
same females for comparison. Evidently the qual-
ity of peanut as a host plant can maintain both
high reproduction and an extended longevity.
The total average fecundity when feeding on
bitter cassava was almost zero; only one female
out of 25 deposited eggs. The total average fecun-
dity was twice as high when feeding on maize and
three times higher when feeding on peanut com-
pared with that of cassava. The pre-experimental
rearing history had a significant impact on the fe-
cundity; females feeding on peanut deposited 37%
more eggs after pre-experimental rearing on pea-
nut than after pre-experimental rearing on
maize. The total average fecundity per host plant
increased with increasing proportion of females
depositing eggs.
The ovipositional midpoint as a percentage of
adult female life span, however, differed signifi-
cantly among hosts; the higher fecundity, the ear-
lier in the life span the eggs were deposited
resulting in a shorter mean generation time (T).
The doubling time (D) of populations reared and
feeding on peanut was twice as short as that of
populations reared and feeding on maize and
nearly four times shorter than the doubling time
of populations feeding on sweet cassava. The
daily population growth ranged from 3.2% in pea-
nut to 1.5% in maize and 0.9% in sweet cassava.
The majority of the insects that had been
reared on peanut and maize prior to the free-
choice test remained in the release space where no
host plant was available. On the contrary, insects
reared on cassava prior to the test showed a clear
preference for peanut and maize over cassava and
the host plant free space where they had been re-
leased. Only females reared on peanut deposited
sufficient eggs to reflect the female positioning
and host selection. These results show a strong
preference for peanut and maize. They also show
that insects which have fed on peanut and maize
are less active in their search for food; they are
probably well fed and better prepared to survive
in a host plant-free space or period of time. After
rearing on peanut and subsequently left to starva-
tion, Riis (unpublished) found the lethal time at
50% mortality to be 80 d for females and 74 d for
males, demonstrating a strong capacity for sur-
vival in the absence of food. Unfortunately, the
study did not include other host plants nor was
the fecundity studied under these circumstances.
Our results show that cassava is not a pre-
ferred host to C. bergi, and insects fed on cassava
are very active in their search for more and better
food. In addition to this, Riis (1990) found that the
thickness of the root peel is an obstacle to the
propagation of C. bergi; first and second instars
were unable to feed on un-peeled roots with a peel
thickness greater than 2 mm, and only 3.3% of











first instars survived on roots with 1-1.5 mm thin
peel. This may be one explanation to why the root
apices, with thinner peel, were more frequently
attacked and damaged than other parts of the
root (Bellotti unpublished). In the case of cassava,
we suggest that weeds in and around the cassava
field may serve as alternative host plants that
could maintain populations ofC. bergi in cassava.

ACKNOWLEDGMENTS

We are grateful to Hector Morales and Carmen Elisa
Mendoza (Pest and Disease Management Unit, CIAT),
who assisted this work in the laboratory, to Lincoln
Smith (Ecologically Sustainable Cassava Plant Project,
CIAT), who assisted with the statistics, and to Peter
Esbjerg (Institute of Ecology and Molecular Biology,
RVAU) for reviewing this manuscript. This project was
jointly funded by the Centro Internacional de Agricul-
tura Tropical (CIAT) and the Danish International De-
velopment Agency (Danida).

REFERENCES CITED

BELLOTTI, A. C., O. VARGAS, B. ARIAS, O. CASTANO, AND
C. GARCIA. 1988. Cyrtomenus bergi Froeschner, A
New Pest of Cassava: Biology, Ecology and Control.
7th Symposium of the International Society for
Tropical Root Crops. Gosier (Guadeloupe), 1-6 July
1985, Ed. INRA, Paris.
BIRCH, L. C. 1948. The intrinsic rate of natural increase
of an insect population. J. Animal Ecol. 17: 15-26
CAREY, J. R. 1993. Applied Demography for Biologists
with Special Emphasis on Insects. Oxford Univer-
sity Press. Oxford. pp. 206.
CIAT. 1980. Cassava Program Annual Report. Centro
International de Agricultura Tropical (CIAT), Cali,
Colombia.
CIAT. 1983. Cassava Program Annual Report. Centro
International de Agricultura Tropical (CIAT), Cali,
Colombia.
CIAT. 1985. Cassava Program Annual Report. Centro
International de Agricultura Tropical (CIAT), Cali,
Colombia.
CIAT. 1989. Cassava Program Annual Report. Centro
International de Agricultura Tropical (CIAT), Cali,
Colombia.


March 2005


CIVIDANES, F. J., S. SILVEIRA, AND P. S. MACHADO. 1981.
Flutuacio populacional de cidnideos coletados em
regioes cana vieiras de Sao Paulo [Population fluctu-
ation of Cydnidae collected in cane regions of Sao
Paulo]. Cientifica, Sao Paulo 9: 241-247.
GARCIA, C. A. 1982. Biologia y Morfologia de Cyr-
tomenus bergi Froeschner (Hemiptera: Cydnidae),
Nueva Plaga de la Yuca. B.Sc. Thesis, Universidad
Nacional de Colombia, Palmira, Colombia, pp. 64.
HERRERA, J. G. 1988. Reconocimiento y manejo de la
chinche subterranea Cyrtomenus bergi Froeschner
en cultivos de 'Cebolla de rama' en Pereira. Institute
Colombiano Agropecuario (ICA), Divisi6n de Sani-
dad Vegetal, Pereira, Colombia, pp. 27.
HULTING, F. L., D. B. ORR, AND J. J. OBRYCKI. 1990. A
computer program for calculation and statistical com-
parison of intrinsic rates of increase and associated
life table parameters. Florida Entomol. 73: 601-612.
ICA. 1980. Notas y Noticias Entomol6gicas (Sept.-Oct.).
Institute Colombiano Agropecuario, Bogota, Colom-
bia. p.68.
KING, A. B. S., AND J. L. SAUNDERS. 1984. The inverte-
brate pests of annual food crops in Central America,
pp. 117-118. Overseas Development Administration,
London, UK.
LACERDA, J. I. 1983. Dano causados au dend6 (Elais
guineesis) por acgo do Cyrtomenus bergi (Froesch-
ner, 1960) (Hemiptera: Cydnidae). Rev. Floresta
(Brazil) 14: 59-60.
MATTESON, J. W. 1966. Flotation technique extracting
eggs ofDiabrotica sp. and other organisms from soil.
J. Econ. Entomol. 59: 223-224.
PEAIRS, F. B., AND M. CARBALLO. 1987. Effects of crop-
ping system and insecticide protection on insects as-
sociated with maize (Zea mays L.) and cassava
(Manihot esculenta Crantz). Turrialba 37: 147-154.
PIANKA, E. R. 1988. Evolutionary Ecology. 4th edition.
Harper Collins Publishers, New York, USA.
RIIS, L. 1990. The Subterranean Burrower Bug Cyrto-
menus bergi Froeschner, An Increasing Pest in Trop-
ical Latin America; Behavioural Studies, Population
Fluctuations, Botanical Control, with Special Refer-
ence to Cassava. M.Sc. Thesis. Royal Veterinary and
Agricultural University, Copenhagen, Denmark.
SAS Institute. 1988. SAS/STATT user's guide, release
6.03 edition. SAS Institute, Inc., Cary, NC, USA.
SMITH, J. W., JR., AND J. T. PITTS. 1971. Pest status of
Pangaeus bilineatus attacking peanuts in Texas. J.
Econ. Entomol. 67: 111-113.


Florida Entomologist 88(1)







Riis et al.: Influence of temperature and soil moisture on C. bergi


INFLUENCE OF TEMPERATURE AND SOIL MOISTURE
ON SOME POPULATION GROWTH PARAMETERS
OF CYRTOMENUS BERGI (HEMIPTERA: CYDNIDAE)

LISBETH RIIS1'2, PETER ESBJERG1 AND ANTHONY CHARLES BELLOTTI2
'Department of Ecology and Molecular Biology
Royal Veterinary and Agricultural University (RVAU), Copenhagen, Denmark

2Centro International de Agricultural Tropical (CIAT), Pest and Disease Management Unit
A.A. 6713 Cali, Colombia S.A.

ABSTRACT

Abundance of Cyrtomenus bergi Froeschner has been reported regularly under moist and
damp conditions. The influence of temperature and soil moisture on development time and
mortality of first, third, and fifth instars, longevity and fecundity of C. bergi adult females,
as well as hatching time and rate of eggs were determined under laboratory conditions at
different temperature and soil moisture levels. Population growth is optimal around 26C
(constant temperature) and a soil moisture regime ranging from moist (field capacity) to wet
soil (between field capacity and water saturation). Wet soil (~44% gravimetric soil water)
promotes high mean fecundity in young adult females, reducing generation time and favor-
ing population growth compared to that seen in moist soil (~33.5% gravimetric soil water,
field capacity). The lower temperature threshold for development was 14.7 C. Neither egg
hatching nor molting from fifth instars to adults occurred above 31 C. The lower soil mois-
ture threshold for immature development was between dusty (-19% gravimetric soil water)
and very dry soil (~22% gravimetric soil water) and between very dry and dry (~25.5% gravi-
metric soil water, wilting point) for adult female survival and oviposition. Third instars were
most tolerant to extreme temperatures. These abiotic limitations to population growth to-
gether with other findings concerning host plant regime and movement in soil may explain
patterns of local and regional abundance.

Key Words: Subterranean burrower bug, soil arthropod, population growth parameters, Cyr-
tomenus bergi

RESUME
Con cierta regularidad se ha reportado la proliferaci6n de Cyrtomenus bergi Froeschner en
condiciones de humedad. Se determine, en condiciones de laboratorio, la influencia de difer-
enctes niveles de temperature y humedad del suleo en la duraci6n del desarrollo y la mortal-
idad del primer, tercer y quinto instar ninfal, en la longevidad y en la fecundidad de hembras
adults de C. bergi, asi como en el moment de eclosi6n y la tasa de eclosi6n de los huevos. El
crecimiento de la poblaci6n es 6ptimo alrededor de 26 C temperaturea constant) y un r6gi-
men de humedad del suelo que fluctua entire suelo humedo (capacidad de campo) y suelo sat-
urado entiree la capacidad de campo y saturaci6n hidrica). Suelo humedo (~44% de agua
gravim6trica del suelo) aumenta la fecundidad promedia de hembras adults jovenes re-
duciendo el tiempo de procreaci6n y favoreciendo el crecimiento de la poblaci6n en el suelo sat-
urado en comparaci6n con el suelo humedo (~33.5% de agua gravim6trica del suelo, capacidad
de campo). El umbral de temperature mas baja para el dasarrollo fue 14.7 C. A partir de los
31 C no hubo eclosi6n de huevos ni muda del quinto instar a adulto. El umbral de humedad
del suelo mas bajo para el desarrollo de los estadios inmaduros fue entire suelo polvoriento
(~19% de agua gravim6trica del suelo) y suelo muy seco (~22% de agua gravim6trica del suelo)
y entire suelo muy seco y suelo seco (~25.5% de agua gravim6trica del suelo, punto de mar-
chitez) para la superviviencia de hembras adults y la oviposici6n. El tercer instar present
la mayor tolerancia frente a las temperatures extremes. Estas limitaciones abi6ticas para el
crecimiento de la pobaci6n, aunados a otros resultados en cuanto al regimen y movimiento de
plants hospedantes en el suelo pueden explicar los models de proliferaci6n local y regional.

Translation provided by the authors.


Cyrtomenus bergi Froeschner is a subterra- bicolor [L.] Moench), welsh onion (Allium fistulo-
nean burrower bug and polyphagous pest reported sum L.), African oil palm (Elaeis guineensis Jacq.),
on cassava (Manihot esculenta Crantz), maize coffee (Coffea spp. L.), sugarcane (Saccharum spp.
(Zea Mays L.), peanut (Arachis hypogaea L.), po- L.), pasture grasses, and weeds (Bellotti & Garcia
tato (Solanum tuberosum L.), sorghum (Sorghum 1983; Lacerda 1983; Herrera 1988). Since the first







Florida Entomologist 88(1)


description of C. bergi as a pest on cassava (CIAT
1980), it has become a serious problem throughout
the neo-tropics (Arias & Bellotti 1985).
C. bergi feeds on roots, tubers, or subterranean
fruits (e.g., peanuts) of host plants. The bug injects
its stylet in the subterranean plant tissue leaving
lesions that facilitate the entrance of soil patho-
gens such as Fusarium, Aspergillus, Genicularia,
and Pythium (CIAT 1980). On peanut kernels, le-
sions appear as delimited dry rot spots (approxi-
mately 1-2 mm diameter), and a heavy attack can
cause complete deterioration of the kernels (per-
sonal observation). On cassava roots, tissue degra-
dation (approximately 5 mm diameter) appears on
the interior white starchy and edible parenchyma
12-24 h after feeding is initiated (Garcia 1982).
All immature stages and the imago of C. bergi
live in the soil. Oviposition also takes place there.
The five instars and the adults feed on the same
host spectrum leaving similar damage symptoms.
Riis et al. (2005) found that C. bergi has a total av-
erage life span of 380 d when feeding on peanut,
324 d when feeding on sweet cassava and 290 d
when feeding on maize (25C and 65 5% RH).
The data base of C. bergi collections at Centro
International de Agricultura Tropical (CIAT), Cali,
Colombia, includes collections from the north-
western part of the South American continent,
with the majority (62%) reported from altitudes of
1000-1700 meters above sea level with average
monthly rainfall above 85 mm throughout the year,
and average monthly temperature ranges from 20-
21C (unpublished). Several reports indicate a re-
lation between abundance of C. bergi and humid
conditions. Clavijo (1981) showed an increased
number of C. bergi in light traps during periods of
high precipitation, and Riis (1990) observed in-
creased cassava root damage due to C. bergi follow-
ing increased precipitation. Cividanes et al. (1981)
also related fluctuations of C. bergi captures to
weather factors, and King and Saunders (1984)
state that C. bergi is more frequently found under
damp conditions. Highland and Lummus (1986)
suggest that soil moisture and rainfall are crucial
factors increasing populations of the burrower bug
Pangaeus bilineatus (Say), also Cydnidae.
A laboratory experiment was conducted to de-
termine the influence of temperature and soil
moisture on development time and mortality of
first, third, and fifth instars, longevity and fecun-
dity of C. bergi adult females as well as hatching
time and hatching rate of eggs. Since C. bergi has
a very long lifecycle, second and fourth instars
were left out of the experiment to reduce time.

MATERIALS AND METHODS
Stock Colony
Cyrtomenus bergi was taken from a stock lab-
oratory colony (23 2C, 65 5% RH, 12 h light)
maintained on germinating seeds of peanuts,


Arachis hypogaea L. (variety 'Tatui SM-76') in un-
sterilized topsoil (loamy clay) kept at a moisture
level approximated to the field capacity (33.5%
gravimetric soil water). The colony originated
from a fallow field at La Bella, Rereira (Province
of Risaralda), Colombia and had been maintained
in culture for one generation.

Experimental Soil
Soil of the Ah-horizon, 0-18 cm, from the CIAT
Field Research Station at Santander de Quilichao
in southern Colombia was used. The soil is de-
scribed as a loamy clay with high content of or-
ganic matter (16.4 kg organic C/m3) (Reining
1992) and pH ranging 4.0-5.2 (Riis 1990). The soil
was passed through an M-4 hammer mill shred-
der (Lindig Mfg Corp., St. Paul, MN) to assure
homogeneous water penetration of soil when irri-
gated in the laboratory.
Water retention characteristics of the experi-
mental soil were determined on air-dried soil
samples. Water content was measured at satura-
tion (0 bar), field capacity (0.33 bar), wilting point
(15 bar), and hygroscopic moisture (>32 bar) with
a pressure plate apparatus (Soil Moisture Corp.,
Goleta, CA). The water-saturated samples were
weighed and placed in plastic rings on porous ce-
ramic plates, permeable to water. Samples were
weighed when the state of equilibrium was
reached, oven dried for 24 h at 105C and re-
weighed. This was repeated three times for each
sample. Water contents were calculated at the dif-
ferent pressures (Richards 1965; Scheffer &
Schachtschabel 1989). A retention curve for this
experimental homogenized soil could not be cal-
culated, since we could not approximate empirical
constants that affect the shape of the retention
curve (Genuchten et al. 1991).
The experimental soil was desiccated at 60C
for 72 h. Subsequently, soil was placed in plastic
containers, weighed, and irrigated while placed
on a scale until the experimental soil water con-
tent was reached. The irrigated soil was left in
closed containers for 48 h prior to use. Before use,
three soil samples were taken to reconfirm the
water content by weighing, drying (105C, 24 h),
and weighing again. After exposure to the bugs
for 2 d (immature stages) and one week (adults),
respectively, three soil samples were taken from
each experimental temperature and moisture
combination to record changes in soil water con-
tent during the experimental time.

Experimental Temperature Levels
Egg eclosion time and rate as well as develop-
ment time and mortality of first, third, and fifth
instars were assessed in temperature controlled
incubators (65 5% RH, 12 h light) at moisture
levels that approximated wilting point (25.9%
gravimetric soil water) and field capacity (33.5%


March 2005







Riis et al.: Influence of temperature and soil moisture on C. bergi


gravimetric soil water), respectively, and at the
following constant temperatures (+1.5C): 13C,
18C, 21C, 23C, 25C, 28C, and 31C. Fecundity
and longevity of post-teneral females of C. bergi
were assessed under similar conditions, but only
at 13C, 21C, 25C, and 31C.

Experimental Soil Moisture Levels

Eclosion time and rate of eggs, development
time and mortality of first, third, and fifth instars
as well as fecundity and longevity of post-teneral
females of C. bergi were assessed in a tempera-
ture and light controlled incubator, 25 + 1.5C, 65
+ 5% RH, 12 h light, at the following approxi-
mated soil moisture levels of gravimetric soil wa-
ter: 19.0% (dusty), 22.0% (very dry), 25.9% (dry,
wilting point), 33.5% (moist, field capacity), 44.0%
(wet), and 60.0%, (water saturated). The soil wa-
ter content of the experimental soil was measured
immediately before and after use.


Optimal Temperature for Immature Development

The optimal temperature for development of
each of the immature stages was found by fitting
a quadratic model (Hyams 1997) to hatching
time/development time weighted against temper-
ature. The temperature corresponding with the
minimum development time of the curve was re-
corded as the optimal temperature for develop-
ment.

Lower Temperature Thresholds and Day-Degrees
Required for Development of Immature Stages

Lower temperature thresholds (To) for devel-
opment of immature stages were estimated by
linear regression on the reciprocal mean develop-
ment time (y) weighted against temperature (T)
y =a+PT
and To was subsequently computed as


Experimental Diet
Experimental Diet


The bugs fed on peanut kernels of which em-
bryos had been removed to avoid water-consum-
ing germination. The peanuts were wrapped in
Parafilm to avoid rapid deterioration.

Development Time and Mortality of Immature Stages

For the determination of the egg hatching time
and rate, recently deposited eggs (<16 h) were re-
covered from soil exposed to adults by searching
the soil carefully with a fine paintbrush. Each of
four non-simultaneous replications comprised 50
eggs placed in groups of 25 in each of two 55-cm2
opaque plastic vials with approximately 30 cm3 of
soil of the experimental moisture level. Egg hatch
was observed daily beyond 7 d after oviposition
and soil also was replaced daily. Hatching time
and rate (percentage) were recorded.
Development time and mortality of first, third,
and fifth instars were determined as follows: Re-
cently emerged first instars (<16 h) were recov-
ered from eggs placed on moist filter paper. Third
and fifth instars were recovered at ecdysis (<16 h
hereafter) from separate stock colonies exclu-
sively containing second and fourth instars, re-
spectively. Nymphs were placed individually in
approximately 30 cm3 of soil of each of the experi-
mental moisture level in opaque plastic vials (55
cm3 volume). Each of four non-simultaneous rep-
lications comprised 20 nymphs. Every 2 d, the
plant diet and soil of experimental moisture lev-
els were renewed after the soil of each plastic-vial
had been searched for exuviae from molting
nymphs. Development time and percent mortal-
ity were recorded for each instar. Each insect was
withdrawn from the experiment at the time of
molting or death.


Development time on a day-degree (DD) time
scale was computed as
DD = DT(T T,) for T > To, else DD = 0,
where DT denotes the observed development time
(days) at the temperature T (Frazer & Gilbert,
1976).

Female Longevity and Fecundity

Fecundity and adult female longevity of 25 fe-
males were assessed at each of the aforemen-
tioned experimental temperatures and soil
moisture levels. Adults were recovered at ecdysis
(<16 h hereafter) from a separate stock colony ex-
clusively containing fifth instars. One female and
two males were placed in approximately 50 cm3
soil in an opaque plastic vial (55 cm3 volume).
Adults were transferred to a new plastic vial with
new soil every week, female survival was recorded
and the food diet was replaced at the same time.
Dead males were replaced with males from the
stock colony. The number of deposited eggs was
counted every two weeks by flotation in a 20% salt
solution of sodium chloride (Matteson 1966).

Statistics

An analysis of variance and subsequent
REGWQ grouping (SAS Institute 1988) were run
separately on each of the studied immature
stages on development time and mortality, on
adult female longevity, and area under the mi-
curve (fecundity weighted with time) for compar-
ison of experimental abiotic conditions. A natural
logarithm transformation was used to homoge-
nize error of female longevity and area under the







Florida Entomologist 88(1)


mx-curve. The transformed data were re-tested
for homogeneity by use of Taylor's Power Law:

= a+x b
The null hypothesis H.: b = 0 was accepted for all
transformed variable confirming homogeneity of
error.

RESULTS

Experimental Soil Moisture Characteristics

The water retention characteristics of the ex-
perimental soil are given in Table 1. Changes in
soil moisture level during the experimental time
are listed in Table 2. Soil moisture levels differed
significantly before and after exposure to imma-
ture stages (soil replaced every 2 d) and adults (soil
replaced weekly) at 25C (see rows; Table 2). With
the exception of dusty soil, the soil water content
was reduced significantly by increasing tempera-
ture due to evaporation (see columns; Table 2).

Development Time and Mortality of Immature Stages
as a Function ofTemperature

The optimal temperature for hatching of eggs
was 25.7C. The optimal temperature for develop-
ment of the first instars was 28.5-29.7C, and
26.4C for third and fifth instars. Third instars
could develop at 13C where other stages failed
(Fig. 1).
The lower temperature threshold was 14.6C
for eggs compared with 13.7C for first and fifth in-
stars and 11.3C for third instars (Table 3). If we
assume that the lower temperature threshold for
each nymphal instar is the same at field capacity
and wilting point (cf. Table 3), a comparison be-
tween wilting point and field capacity of the devel-
opment time on a day-degree scale of each instar
showed that the development times of first and
third instars on a day-degree scale were signifi-
cantly longer at wilting point than at field capacity
(8.67 < F < 20.76, df= 6, P < 0.0258) (cf Table 3).
Development time and mortality decreased
with temperature within the temperature regime
18-25C (Fig. 1). The highest egg hatching rate


TABLE 1. GRAVIMETRIC SOIL WATER CONTENT (%) OF THE
EXPERIMENTAL SOIL UNDER DIFFERENT PRES-
SURES (BAR).

Soil moisture level Bar %

Hygroscopical moisture >32 9.9 2.76
Wilting Point (WP) 15 25.9 0.17
Field Capacity (FC) 0.3 33.5 + 0.16
Saturation 0 70.2 1.01

Values are means of 3 replications + standard errors.


('inverse mortality') occurred at 25C and no
hatching occurred at 31C. The lowest mortality
of first and fifth instars occurred at 25C, and at
28C for third instars (Fig. 1). At temperatures
where egg hatching and ecdysis of nymphs oc-
curred, mortality did not differ significantly be-
tween wilting point and field capacity.
Exceptionally long survival times occurred at
the extreme temperatures. At 13C, below the
lower temperature threshold of eggs, the mean
survival time of first instars until death was 24 d
(SE 2.98) at wilting point and 35 d (SE 3.86) at
field capacity. The mean survival time of fifth in-
stars until death at 13C was 230 d (SE, 16.6) at
wilting point and 232 d (SE, 13.9) at field capac-
ity. Fifth instars could not molt at 31C and the
mean survival time of fifth instars until death at
31C was 60 d (SE, 2.05) at wilting point and 69
d (SE, 2.27) at field capacity

Development Time and Mortality of Immature Stages
as a Function of Soil Moisture

Cyrtomenus bergi developed at a wide range of
soil moisture levels with the exception of dusty
soil. Egg hatching did not occur in very wet soil
(Fig. 2). Egg hatching time was significantly
shorter (by 1 d) in moist and wet soil than that in
very dry soil (F = 2889, df = 18, P < 0.0001), and
the hatching time in dry soil did not differ from
any of these. The highest egg hatching rates ('in-
verse mortality', Fig. 2) occurred in the moisture
range from dry soil (wilting point) to moist soil
(field capacity) (inclusive), and were significantly
higher than those in wet soil. Hatching rates in
wet soil were higher than those in very dry soil (F
= 395.9, df= 18, P < 0.0001).
Development times of nymphs (Fig. 2) did not
differ significantly above wilting point (dry soil),
and these were shorter than those below wilting
point (24.76 < F < 68.16, df= 18, P < 0.0001). At all
temperature levels, the development of the first
instars was slightly prolonged at wilting point
compared with field capacity (cf. Fig. 1), but these
did not differ significantly. The lowest mortality of
the first instars occurred in moist soil (Fig. 2) and
was significantly lower than those in very wet and
very dry soil (F = 20.38, df = 18, P < 0.0001). The
lowest mortality of third and fifth instars oc-
curred in soil moisture regime from dry (wilting
point) to wet soil (Fig. 2), which did not differ sig-
nificantly, and these were lower than that in very
dry soil (32.40 < F < 57,32, df= 18, P < 0.0001).

Female Longevity and Survival by Age as a Function of
Temperature

Recorded female longevity was longest at 21C,
but did not differ significantly from those at 25C
and that at 13C at field capacity (Fig. 3a). Female
survival by age (Lw) showed little mortality until


March 2005



















TABLE 2. SOIL WATER CONTENT (%, GRAVIMETRIC) OF EXPERIMENTAL SOIL MOISTURE LEVELS; INITIALLY AND AFTER EXPOSURE TO C. BERGI AT DIFFERENT TEMPERATURES.

Soil water content (%, gravimetric)

ANOVA'
Soil samples
taken at ... Dusty Very dry Dry (WP) Moist (FC') Wet Very wet df F

Initially 18.7 0.22 a'Ad 22.0 0.11 aB 25.5 0.08 aC 34.3 0.08 aD 44.1 0.22 aE 61.2 0.22 aF 2714 9263****
130C 25.2 0.11 a 33.1 0.10 b -
180C 25.1 0.10 a 32.9 0.08 b -
210C 24.5 0.08 b 32.3 0.09 c -
230C 24.2 0.17 bc 31.7 0.12 d -
250C 18.3 0.54 aA 20.5 0.21 bB 24.1 0.07 bcC 31.5 0.28 dD 42.3 0.35 bE 58.7 0.27 bF 790 4326****
280C 23.8 0.24 cd 31.5 0.16 d -
310C 23.4 0.12 d 30.7 0.28 e -

ANOVA'
df 29 366 3249 2956 305 313
F 0.75 NS 49.02**** 51.35**** 104.86**** 17.08**** 32.33****

Values are means + standard errors.
aWP denotes approximated wilting point.
FC denotes approximated field capacity.
'REGWQ-grouping: Means with the same lower-case letter in the same column are not significantly different.
dREGWQ-grouping: Means with the same capital letter in the same row are not significantly different.
e**** denotes P < 0.0001; ns, not significant.







Florida Entomologist 88(1)


100
90
80
70
60
50
40
30
20
10
0


13 18 212325 28 31


100 70
90 60
80
70 50
60 40
50
40 30
30 20
20
10 10
0 0


13 18 212325 28 31


13 18 212325 28 31


13 18 212325 28 31


Temperature (oC)

Fig. 1. Development time (dots, left axis) and mortality (bars, right axis) of some immature stages of C. bergi as
a function of temperature and soil moisture levels approximated to field capacity (FC, black) and wilting point (WP,
grey). Optimum temperatures are given at field capacity and wilting point, respectively. Dots are means and bars
are percentage of 200 eggs and 80 individuals of each instar, respectively. Vertical lines denote standard errors.


approximately 180 d and then fairly steep mortal-
ity thereafter, with exception of extreme tempera-
tures, 13C and 31C (Fig. 4a). Initially female
survival by age (Lx) started declining more steeply
at 13C than at 31C, both at wilting point. Never-
theless, after approximately 40 d, female survival
at 13C at wilting point declined slowly, while fe-
male survival at 31C at wilting point declined rap-
idly and the population died out soon after (Fig. 4a).

Female Longevity and Survival by Age as a Function of
Soil Moisture

Adult female longevity was shorter in very dry
soil than at other soil moisture levels (F = 144.7,
df = 120, P < 0.0001), which did not differ signifi-
cantly from each other (Fig. 3b). Longevity did not
differ significantly between field capacity and


wilting point at 21-25C. At more extreme tem-
peratures, 13C and 31C, females lived longer at
field capacity than at wilting point (F = 35,97, df
= 192, P < 0.0001) (Fig. 3a).
At all soil moisture conditions female survival
by age (Lw) showed little mortality until approxi-
mately 180 d and then fairly steep mortality
thereafter, with exception of very dry soil in which
females died out after 56 d only (Fig. 4b).

Fecundity as a Function of Temperature

Total fecundity differed significantly between
temperature levels (F = 87.40, df = 192, P <
0.0001). It was highest at 21C and 25C and did
not differ significantly between these two tempera-
ture levels (Fig. 3a). All females deposited eggs at
21C and 25C at field capacity. Between 84-92%


March 2005







Riis et al.: Influence of temperature and soil moisture on C. bergi


TABLE 3. ESTIMATION OF LOWER TEMPERATURE THRESHOLDS (To) AND DEVELOPMENT TIME ON A DAY-DEGREE (DD)
SCALE OF IMMATURE STAGES OF C. BERGI FEEDING ON PEANUT AT APPROXIMATED SOIL MOISTURE LEVELS OF
FIELD CAPACITY (FC) AND WILTING POINT (WP), RESPECTIVELY.

Soil
Instar moisture level n Regression r2 P To DD

Egg FC 200 y = -0.1160 + 0.0077T 0.998 0.0012 14.7 126.9 1.75
WP 200 y = -0.1092 + 0.0076 T 0.996 0.0020 14.4 132.9 2.21
1 FC 80 y = -0.0939 + 0.0069 T 0.980 0.0099 13.7 153.0 4.29
WP 80 y = -0.0798 + 0.0061T 0.996 0.0020 13.2 186.1 5.86
3 FC 80 y = -0.0790 + 0.0069 T 0.971 0.0021 11.4 155.5 7.27
WP 80 y = -0.0647 + 0.0058 T 0.954 0.0043 11.1 188.1 + 8.35
5 FC 80 y = -0.0525 + 0.0038 T 0.997 0.0018 13.7 265.8 3.08
WP 80 y = -0.0515 + 0.0037 T 0.997 0.0018 13.9 274.4 4.00

n, sample size.
"Values are means + standard errors.


females deposited eggs at 21C and 25C at wilting
point, and at 31C at field capacity. Only 8-12% of
females deposited eggs at 31C at wilting point and
at 13C at both wilting point and field capacity
(Fig. 3a), resulting in less than 0.25 eggs per female
on average. At 31C females deposited significantly
more eggs at field capacity than at wilting point.
At all soil temperature and soil moisture com-
binations, with mean fecundity per female >1,
mean fecundity by age (Mx) showed a small peak
after approximately 40-55 d and a large peak af-
ter approximately 180-210 d (Fig. 5a, b), with ex-
ception of 31C at field capacity where only one
peak occurred after 112 d (Fig. 5a).

Fecundity as a Function of Soil Moisture

Total fecundity differed between soil moisture
levels (F = 51.39, df = 120, P < 0.0001) (Fig. 3b).
Most eggs were deposited in moist (field capacity)
and wet soil, and significantly fewer eggs were de-
posited in very wet soil. Number of eggs deposited
in dry soil was intermediate and did not differ sig-
nificantly from moist, wet or very wet soil. No
eggs were deposited in very dry soil.
All females oviposited in moist soil (field ca-
pacity). Between 84-92% of the females oviposited
in wet, very wet and dry (wilting point) soil (Fig.
3b). No females oviposited in very dry soil.
Mean fecundity by age (M.) in wet soil was
high during early age of female lifespan until its
large peak at approximately 182 d, and coincided
thereafter with those of moist and dry soil (Fig.
5c). Mean fecundity by age in very wet soil was in-
ferior to those of other soil moisture levels with
mean fecundity per female >1.

DISCUSSION

The optimal temperature for development of
first instars was 28-29C and 26C for other in-


stars. The optimal temperature for the adult
stage could not be determined from the few tem-
perature levels tested, but it is likely to be within
the range of that for development. Due to the lack
of parameters for second and fourth instars, we
could not calculate population increase rates.
In general, the development of C. bergi was
limited to a temperature regime ranging between
14.7C and just below 31C. Egg hatching could
not occur at 31C. Fifth instars lived longer at
31C than at any other temperatures above the
lower temperature threshold, but were unable to
molt. At high temperature, 31C, both fecundity
and longevity were reduced compared with the
21-25C temperature regime indicating that the
upper temperature threshold was between 25 and
31C. The third instar is the most robust instar,
showing high tolerance to extreme temperature
conditions.
The optimal soil moisture level for develop-
ment of immature stages was moist soil (field ca-
pacity) and moist to wet soil for the adult stage.
The high mean fecundity in the early age of the
female lifespan in wet soil reduces the generation
time and favors population growth in wet soil
over moist soil. Female longevity was not reduced
in very wet soil, but the number of oviposited eggs
was significantly less. Cyrtomenus bergi did not
tolerate extremely dry conditions. Very dry soil
reduced longevity of adult females significantly
and no eggs were deposited.
Villani and Wright (1990) speculate that
heavily sclerotized soil insects should be less vul-
nerable to moisture loss of the cuticle under dry
conditions. We, on the contrary, found that the
heavily sclerotized C. bergi adults were more sen-
sitive to drought than less sclerotized immature
stages. The lowest soil moisture threshold for
adult survival and oviposition was just below dry
soil (~25.5% gravimetric soil water, wilting point),
whereas the lowest soil moisture threshold for the







Florida Entomologist 88(1)


Egg stage


i 0 '0 t D


3rd instar










r ~ ~ ~ ~ [ Pi i ---


- 10024 -
- 90 21 -
- 80 18 -
70
-60 15 -
-50 12 -
-40 9-
-30
-20
-10 3
0 0

- 10040
- 90 35
-80
- 70 30 -
- 60 25 -
- 50 20 -
-- 40
-40 15 -
- 30
20 10 -
10 5
0 0-


1st instar


Lc 0 LOC 0 O 0 C 0 C) O 0 L
N-- CNI CM) M" '-t 4" 1) 1) (0 a


- 100
- 90
- 80
- 70
- 60
- 50
- 40
- 30
- 20
-10
0


- 100
- 90
- 80
- 70
- 60
- 50
- 40
- 30
- 20
10
0


0>0


>

Q>QI


4-


3 >


Soil moisture (%, gravimetric)

Fig. 2. Development time (dots, left axis) and mortality (bars, right axis) of some immature stages of C. bergi as
a function of soil moisture levels and 25 C. WP and FC denote soil moisture levels approximated wilting point and
field capacity, respectively. Dots are means and bars are percentage of 200 eggs and 80 individuals of each instar,
respectively. Vertical lines denote standard errors.


development of immature stages was just below
very dry soil (~22% gravimetric soil water). De-
spite the lower soil moisture threshold for imma-
ture stages compared with adults, young
nymphal stages (first and third instars) did un-
dergo some stress in dry soil as the development
time on a day-degree scale was significantly
longer at wilting point than at field capacity.
Although the total fecundity did not differ sig-
nificantly between field capacity and wilting
point within the temperature regime 21-25C,
during the initial female adult age (<150 d), we
observed a higher mean fecundity at wilting point


than at field capacity at 21C opposite of what
was observed at 25C. Otherwise, soil moisture
ranging from wilting point to field capacity played
a significant role only for the adult stage at ex-
treme temperatures, 13C and 31C. At high tem-
perature (31C), both total fecundity and female
longevity was significantly reduced at wilting
point compared to field capacity. At low tempera-
ture (13C), longevity, but not fecundity, was sig-
nificantly reduced at wilting point compared to
field capacity.
Our experimental design of leaving each fe-
male individually with two males, to assure suc-


C0
- C-
In


i


24 -
21 -
18
15 -
12 -
9-
6-
3-
0


March 2005






Riis et al.: Influence of temperature and soil moisture on C. bergi


300 -

250 -

200 -

150 -

100 -

50-

0 -




300

250


21 25
Temperature (0C)


LO 0 LO 0 0 0 LO 0 1O 0 o 0
N- C\ CJ CO CO q 't LO U) CO CD


>0
3a i


Soil moisture (%, gravimetric)
Fig. 3. Means of female longevity (dots, left axis) and total fecundity (bars, right axis) of 25 females of C. bergi
as a function of (a) temperature at approximated field capacity (black symbols and bars) and wilting point (grey
symbols and bars), and as a function of (b) soil moisture at 25 C. WP and FC denote soil moisture levels approxi-
mated wilting point and field capacity, respectively. Percentages of females ovipositing are given in bold numbers
below bars. Vertical lines denote standard errors.


cessful copulation, apparently disturbed the
oviposition of the female. Fewer eggs were recov-
ered in this design compared to previous studies
(Riis et al. 2005) with the same host plant and the
same methodology for egg recovery, but only one
male per female. The present design did not re-
flect the 1:1 sex ratio found in the field (Riis et al.
2005). Providing a diet of dry peanut kernels in-


stead of germinating kernels as Riis et al. (2005)
might also have influenced the ovipositional rate.
This is the first study reporting effects of soil
moisture on subterranean Hemiptera. It is worth
noticing that the effect of soil moisture on popula-
tion growth parameters of subterranean arthro-
pods differ remarkably among orders, for
example white grubs (Cherry et al. 1990; Potter


8% 8%


92% 100% 84%100%


200

150

100

50

0


12% 88%


- 200
- 180
- 160
- 140
- 120
- 100
- 80
- 60
- 40
- 20
-1
-0


200
180
160
140
120
100
80
60
40
20
0







Florida Entomologist 88(1)


1.0

0.9-

0.8-

0.7-

0.6-

0.5 -

0.4-

0.3-

0.2-

0.1 -

0.0 -
1.0

0.9-

0.8

0.7 -

0.6

0.5 -

0.4 -

0.3 -

0.2 -

0.1 -

0.0 -


Wet
-o- Moist, FC
-o- Dry,WP
--0 Very wet
-- v Very dry


V

0 28 56 84 112


44.1% -
34.3 %
25.5 % 25 C
61.2%
22.0 %


Q~t


140 168 196 224 252 280 308 336 364 392 420 448



140 168 196 224 252 280 308 336 364 392 420 448


Age (days)

Fig. 4. Survival of 25 females of C. bergi during their life span as a function of (a) temperature at soil moisture
levels approximated field capacity (FC, black symbols) and wiling point (WP, grey symbols), respectively, and as a
function of (b) soil moisture levels (%, gravimetric) at 25 C.


1983; Reginiere et al.1981), larvae of Chrysomel-
idae (Brust & House 1990; Lummus et al. 1983;
Macdonald & Ellis 1990; Marrone & Stinner
1984), Curculionidae (Dowd & Kok 1983), and
cutworms (Esbjerg 1989).
The above results, together with previous find-
ings on active horizontal movement of C. bergi to-
wards moist and wet soil, vertical emigration away
from very dry soil conditions (Riis & Esbjerg 1998),
and host plant regimes (Riis et al. 2005) may ex-
plain patterns of local and regional abundance.


Supported by our findings, we can conclude
that C. bergi is well adapted for moist soil condi-
tions, which explains its regional as well as local
distribution. Moist soil conditions and a history of
C. bergi infestation require monitoring of C. bergi
in growers' fields and preventive treatment dur-
ing early infestation.
Antagonistic soil pathogens and nematodes,
which also favor moist conditions, such as the en-
tomophilic fungi, Metarhizium anisoplia, and the
nematodes, Steinernema carpocapse and Hetero-


I I I I I I I I I I I I i l I I I I II 1 I I I I I I I 1


I


~


m_


March 2005








Riis et al.: Influence of temperature and soil moisture on C. bergi


2 -
0 ,T,T T,T ,T,

16] b





6





14 C
12
10
8 -



16



4
2- ,
0


W
-- M
0 V
0V




0
S o


0 28 56 84 112 140 168 196 224 252 280
Age (days)

Fig. 5. Fecundity of 25 females of
their life span as a function of (a) tei
moisture levels approximated field ca
symbols) and (b) wilting point (WP, g
spectively, and as a function of (c)
gravimetric) at 25C.



rhabditis bacteriophora, effectively
under laboratory conditions (Ba
Caicedo & Bellotti 1994; Sanche:
duction and infection rates of these
cantly between strains depen
climatic origin and thermal niche
1994; Kung et al. 1991; McCammoi
Studies for the control of C. bergi
agents should therefore include cc
the influence of abiotic conditions
bio-agent strains, and their intera


ACKNOWLEDGMENT:


We are grateful to H6ctor Morale
P6rez (Pest and Disease Management
assisted this work in the laboratory at
ona (Department of Soil Physics, Univ
Palmira, Colombia), who facilitated d
retention. This project was funded by 1


national Development Agency (Danida) and hosted by
25 C the Pest and Disease Management Unit at Centro Inter-
21 FC national de Agricultura Tropical in Colombia.
13 OC-0
REFERENCES CITED

ARIAS, B., AND A. C. BELLOTTI. 1985. Aspectos ecol6gicos
y de manejo de Cyrtomenus bergi Froeschner, chinche
de la viruela en el cultivo de la yuca (Manihot escu-
lenta Crantz). Rev. Colombiana Entomol. 11: 42-46.
BARBERENA, M. A. 1996. Capacidad Parasitica de dos
S Razas del Nematodo Heterorhabditis bacteriophora
Poinar (Rhabditida: Heterorhabditidae) Sobre la
21 C P Chinche de la Viruela de la Yuca Cyrtomenus bergi
--- 31 Froeschner (Hemiptera: Cydnidae) en condiciones
13 C de laboratorio. B.Sc. Thesis, Universidad de Valle,
Cali, Colombia.
BELLOTTI, A. C., AND C. A. GARCIA. 1983. The subterra-
nean Chinch Bug, a new pest of cassava. Cassava
Newsletter 7: 10-11.
BRUST, G. E., AND G. J. HOUSE. 1990. Effects of soil mois-
ture, texture, and rate of soil drying on egg and larval
S :,- survival of the southern corn rootworm (Coleoptera:
et 44.1 % Chrysomelidae). Environ. Entomol. 19: 697-703.
olst, FC 343%] CAICEDO, A. M., AND A. C. BELLOTTI. 1994. Evaluacion
ry, W 25. del potential del nematodo entom6geno Steinernema
erydry 22.0% carpocapse Weiser (Rhabditida: Steinernematidae)
para el control de Cyrtomenus bergi Froeschner
(Hemiptera: Cydnidae) en condiciones de laborato-
rio. Rev. Colombiana Entomol. 20: 241-246.
CHERRY, R. H., F. J. COALE, AND P. S. PORTER 1990.
Oviposition an survivorship of sugarcane grubs (Co-
o leoptera: Scarabaeidae) at different soil moistures.
J. Econ. Entomol. 83: 1355-1359.
'i CIAT. 1980. Cassava Program Annual Report. Centro
308 336 364 392 420 448 Internacional de Agricultura Tropical (CIAT), Cali,
Colombia.
CIVIDANES, F. J., S. SILVEIRA, AND P. S. MACHADO. 1981.
C. bergi through Flutuacio populacional de cidnideos coletados em
nperature at soil regioes cana cieiras de Sao Paulo. Cientifica, Sao
pacity (FC, black Paulo 9: 241-247.
rey symbols), re- CLAVIJO, S. 1981. Variaciones estacionales de poblaciones
soil moisture (%, de adults de Spodoptera frugiperda Cyrtomenus
bergi en cinco localidades de los alrededores del lago de
Valencia, medidas mediante trampas de luz. Revista
de la Facultad de Agronomia (Maracay) 12: 63-79.
y infect C. bergi DOWD, P. F., AND L. T. KOK. 1983. Influence of soil con-
rberena 1996; editions on Carduus thistles and development of the
rberena 1996; thistle head weevil, Rhinocyllus conicus (Coleoptera:
z 1996). Repro- Curculionidae). Environ. Entomol. 12: 439-441.
se differ signifi- ESBJERG, P. 1989. The influence of soil moisture on mor-
ding on their tality and on the damaging effect of second and 6th
s (Grewal et al. instar cutworms (Agrotis segetum Schiff, Lep.: Noc-
n & Rath 1994). tuidae). Acta Ecol./ Ecol. Appl. 10: 335-347.
with such bio- FRAZER, B. D., AND N. GILBERT. 1976. Coccinellids and
)nsiderations of aphids: a quantitative study of the impact of adult
on C. bergi, the ladybirds (Coleoptera: Coccinellidae) preying on
actions. field populations of pea aphids (Homoptera: Aphid-
ctons idae). J. Entomol. Soc. British Columbia 73: 33-56.
GARCIA, C. A. 1982. Biologia y Morfologia de Cyrto-
S menus bergi Froeschner (Hemiptera: Cydnidae),
Nueva Plaga de la Yuca. B.Sc. Thesis, Universidad
s and Gerardino Nacional de Colombia, Palmira, Colombia.
Unit, CIAT), who GENUCHTEN, M. TH. VAN, F. J. LEIJ, AND S. R. YATES.
nd to Miguel Bar- 1991. The RETC code for quantifying the hydraulic
ersidad Nacional, functions of unsaturated soils. USDA, Riverside, CA.
ata on soil water GREWAL, P. S., S. SELVAN, AND R. GAUGLER. 1994. Ther-
the Danish Inter- mal adaptation of entomopathogenic nematodes:











niche breadth for infection, establishment, and re-
production. J. Thermal Biol. 19: 245-253.
HERRERA, J. G. 1988. Reconocimiento y manejo de la
chinche subterranea Cyrtomenus bergi Froeschner
en cultivos de 'Cebolla de rama' en Pereira. Institute
Colombiano Agropecuario (ICA), Pereira, Colombia.
HIGHLAND, H. B., AND P. F. LUMMUS. 1986. Use of light
traps to monitor flight activity of the burrower bug,
Pangaeus bilineatus (Hemiptera: Cydnidae), and as-
sociated field infestations in peanuts. J. Econ. Ento-
mol. 79: 523-526.
HYAMS, D. 1997. CurveExpert 1.34. Starkville, MS.
Web:http://www.ebicom.net/~dhyams/ cvxpt.htm.
KING, A. B. S., AND J. L. SAUNDERS. 1984. The inverte-
brate pests of annual food crops in Central America.
Overseas Development Administration (ODA), Lon-
don, UK.
KUNG, S. P., R. GAUGLER, AND H. K. KAYA. 1991. Effects
of soil temperature, moisture, and relative humidity
on entomopathogenic nematode persistence. J. In-
vertebrate Pathol. 57: 242-249.
LACERDA, J. I. 1983. Dano causados au dend6 (Elais
guineesis) por acgo do Cyrtomenus bergi (Froesch-
ner, 1960) (Hemiptera: Cydnidae). Rev. Floresta
(Brazil) 14: 59-60.
LUMMUS, P. F., J. C. SMITH, AND N. L. POWELL. 1983.
Soil moisture and texture effects on survival of im-
mature southern corn rootworms, Diabrotica undec-
impunctata howardi Barber (Coleoptera: Chryso-
melidae). Environ. Entomol. 12: 1529-1531.
MACDONALD, P. J., AND C. R. ELLIS. 1990. Survival time
of unfed first-instar Western Corn Rootworm (Co-
leoptera: Chrysomelidae) and the effects of soil type,
moisture, and compaction on their mobility in soil.
Environ. Entomol. 19: 666-671.
MARRONE, P. G., AND R. E. STINNER 1984. Influence of
soil physical factors on survival and development of
the larvae and pupae of the bean leaf beetle, Cero-
toma trifurcata (Coleoptera: Chrysomelidae). Cana-
dian Entomol. 116: 1015-1023.
MATTESON, J. W. 1966. Flotation technique extracting
eggs of Diabrotica sp. and other organisms from soil.
J. Econ. Entomol. 59: 223-224.
MCCAMMON, S. A., AND A. C. RATH. 1994. Separation of
Metarhizium anisoplia strains by temperature depen-
dent germination rates. Mycol. Res. 98: 1253-1257.


March 2005


POTTER, D. A. 1983. Effect of soil moisture on oviposi-
tion, water absorption, and survival of southern
masked chafer (Coleoptera: Scarabaeidae) eggs. En-
viron. Entomol. 12: 1223-1227.
REGNIERE, J., R. L. RABB, AND R. E. STINNER 1981. Pop-
illia japonica: effect of soil moisture and texture on
survival and development of eggs and first instar
grubs. Environ. Entomol. 10: 654-660.
REINING, L. 1992. Erosion in Andean hillside farming:
characterization and reduction of soil erosion by wa-
ter in small-scale cassava cropping systems in the
southern central cordillera of Colombia. Verlag Josef
Margraf, Weikersheim, Germany.
RICHARDS, L. A. 1965. Physical condition of water in
soil. Methods of soil analysis. C. A. Black. Madison,
Wisconsin, Am. Soc. Agron. I: 128-152.
RIIS, L. 1990. The Subterranean Burrower Bug Cyr-
tomenus bergi Froeschner, An Increasing pest in
Tropical Latin America; Behavioural Studies, Pop-
ulation Fluctuations, Botanical Control, with Spe-
cial Reference to Cassava. M.Sc. Thesis, Royal
Veterinary and Agricultural University, Copen-
hagen.
RIIS, L., B. ARIAS, AND A. C. BELLOTTI. 2005. Bionomics
and population growth statistics of the subterranean
burrower bug Cyrtomenus bergi on different host
plants. Florida Entomol. 88(1): 1-10.
RIIS, L., AND P. ESBJERG. 1998. Movement, distribution,
and survival of Cyrtomenus bergi (Hemiptera: Cyd-
nidae) within the soil profile in experimentally sim-
ulated horizontal and vertical soil water gradients.
Environ. Entomol. 27(5): 1175-1181
SANCHEZ, D. 1996. Patogenecidad de Hongos Hypho-
mycetes Sobre Cyrtomenus bergi Froeschner
(Hemiptera: Cydnidae) Chinche Subterranea de la
Yuca en Condiciones de Laboratorio. B.Sc. Thesis,
Universidad Nacional de Colombia, Palmira, Colom-
bia.
SAS INSTITUTE. 1988. SAS/STATTM user's guide, re-
lease 6.03 ed. SAS Institute, Inc., Cary, NC, USA.
SCHEFFER, F., AND P. SCHACHTSCHABEL. 1989. Lehr-
buch der Bodenkunde. Enke, Stuttgart, pp. 171-205.
VILLANI, M. G., AND R. J. WRIGHT. 1990. Environmen-
tal influences on soil macro arthropod behaviour in
agricultural systems. Ann. Rev. Entomol. 35: 249-
269.


Florida Entomologist 88(1)







Chen et al.: New species of Caristianus from China


TWO NEW SPECIES OF CARISTIANUS
(HEMIPTERA: FULGOROIDEA: ACHILIDAE) FROM
MAOLAN NATIONAL NATURE RESERVE IN GUIZHOU, CHINA

XIANG-SHENG CHEN2, ZI-ZHONG LI1 AND JAMES H. TSAI3
'Institute of Entomology, Guizhou University, Guiyang, Guizhou Province 550025, P.R. China

2Institute of Zoology, Chinese Academy of Sciences, Beijing 10080, P.R. China

3Fort Lauderdale Research and Education Center, IFAS, University of Florida
3205 College Avenue, Fort Lauderdale, FL 33314, USA

ABSTRACT

Two new species of Caristianus Distant (Hemiptera: Fulgoroidae: Achilidae), C. maolanensis
Chen and Li sp. nov. and C. liaoi Chen and Tsai sp. nov., are described from specimens col-
lected in Maolan National Nature Reserve in Guizhou Province, China. Male genitalia of the
new species are illustrated and a dorsal habitus is provided for the male of C. maolanensis.
A key for identifying the species of Caristianus is included.

Key Words: Caristianus, new species, Achilidae, Hemiptera, Southwest China

RESUME

Se described dos nuevas species de Caristianus Distant (Hemiptera: Fulgoroidae: Achili-
dae), C. maolanensis Chen y Li sp. nov. y C. liaoi Chen y Tsai sp. nov., de especimenes re-
colectados en la Reserva Natural Nacional de Maolan en la Provincia de Guizhou, China.
Las genitalias de los machos de estas species nuevas son ilustratradas y se provee una ilus-
traci6n del habitus dorsal del macho de C. maolanensis. Se incluye una clave para identificar
las species del g6nero Caristianus.


The genus Caristianus was established by Dis-
tant (1916) based on specimens of C. indicus Dis-
tant from Ceylon. Ten species, including 1 variety,
were formerly recorded in the world, mainly in
the Oriental region and the Palearctic region
(China, Borneo, Ceylon, India, Philippines, Sara-
wak, Kalimantan, Afghanistan and Japan) (Dis-
tant 1916; Fennah 1949, 1950, 1956, 1965;
Ishihara 1954; Dlabola 1957; Chou et al. 1985,
1994; Chen & Lin 2001).
To date, the majority of species in the genus,
with the exception of C. japonicus Ishihara (Ja-
pan: Shikoku) and C. cardinalis Fennah (Philip-
pines: Luzon), are described from specimens
collected in China, namely C. indicus Distant
(Jiangxi), C. ulysses Fennah (Sichuan, Yunnan),
C. fopingensis Chou et al. (Shaanxi), C. ziyangen-
sis Chou et al. (Shaanxi, Yunnan), C. asymmetries
Chou et al. (Yunnan), C. symmetries Chou et al.
(Yunnan), C. nigripectus Chou et al. (Yunnan),
and C. jilinensis Chou et al. (Jilin) (Fennah 1956;
Chou et al. 1985, 1994; Chen & Lin 2001).
During the course of studying biodiversity in
Maolan National Nature Reserve in Guizhou
Province, southwest China, two fulgorid speci-
mens belonging to the unknown species of the ge-
nus Caristianus Distant were found. The purpose
of this paper is to describe two new species and to


provide an identification key to the species of Car-
istianus.

MATERIALS AND METHODS

Morphological techniques and terminology fol-
lows Fennah (1950) and Chou et al. (1994). Spec-
imens examined are deposited in the Insect
Collection at the Institute of Entomology,
Guizhou University, Guiyang, Guizhou Province,
China (IEGU).

DESCRIPTIVE TAXONOMY

Caristianus Distant

Caristianus Distant, 1916, 6: 63. Type species: C. indi-
cus Distant, 1916, by original designation.

Caristianus Distant: Fennah, 1950, Bull. Brit. Mus.
(N.H.) Ent., 1:103.

Caristianus Distant: Chou et al., 1994, Entomotaxono-
mia, 16(1): 38.

The distinctive characters used by Fennah (1950)
and Chou et al. (1994) are modified as follows:
Head with eyes distinctly narrower than
pronotum. Vertex slightly declivous, longer in











middle than broad across base (1.2-1.9:1), pro-
duced before eyes for about half of their length;
median carina present, obsolete distally; disk
strongly depressed; anterior margin carinate,
strongly convex; lateral margins carinate,
straight, diverging basad; posterior margin trans-
verse. Frons moderately convex in profile, longer
in middle line than broad (1.3-1.9:1), widest part
about three times as wide as base; basal margin
convex-truncate; median carina distinct, percur-
rent; lateral margins carinate, sinuately diverg-
ing to level of antennae then gradually incurved
to suture, rather obliquely foliate; disk of frons
not depressed. Clypeus more than half as long as
frons, medially and laterally carinate. Rostrum
with subapical segment shorter than apical. An-
tennae subglobose, not sunk in a depression.
Ocelli touching eyes. Eyes distinctly excavate be-
neath, only slightly overlapping pronotum.


March 2005


Pronotum moderately short, about as long be-
hind eyes as in middle line; anterior margin of disk
truncate, posterior margin angulately excavate;
median carina present; lateral carinae of disk
straight, diverging basad, attaining hind margin,
each not quite as long as median carina; two in-
complete carinae between eye and tegula; prono-
tum laterad of disk slightly inclined antero-
ventrally; ventral margin of lateral lobes slightly
oblique. Mesonotum longer than vertex and prono-
tum together, tricarinate, lateral carinae straight,
weakly divergent. Tegulae not carinate. Posttibiae
with a single spine basad of middle.
Tegmina 3 times as long as broad, costal mar-
gin slightly convex; Sc+R fork near basal quarter,
basad of union of claval veins; M forked level with
node; Cul fork basad of apex of clavus and distad
of union of claval veins; 7 apical areoles distad of
stigma. Clavus terminating distad of middle.


KEY TO SPECIES OF Caristianus DISTANT

1. Pronotum and mesonotum with lateral areas outside lateral carinae blackish brown or purplish brown,
central areas ivory-yellow or milky white (Fig. 1; Chou et al. 1994: Fig. 1: E; Ishihara 1954:
Fig. 16: 1); costal areas of tegmina with ivory-yellow longitudinal band, enlarging from base
to apex (Fig. 1; Chou et al. 1994: Fig. 1: E; Distant 1916: Fig. 48) ................................. 2
-Pronotum and mesonotum blackish or stramineous (Fig. 8); costal areas of tegmina without ivory-yellow
longitudinal band, but with some milky white markings (Fig. 10; Ishihara 1954: Fig.16: 4;
Fennah 1965: Fig. 68) ................................................................. 10
2. Frons almost blackish brown or brown (Fig. 2; Chou et al. 1994: Fig. 1: F; Distant 1916: Fig. 48) ............ 3
-Frons blackish brown or purplish brown, except apically with yellowish white transverse band
(Fig. 9; Ishihara 1954: Fig. 16: 2; Fennah 1965: Fig. 66) ...................................... 7
3. Median carina of frons distinct, percurrent; clypeus without yellow transverse markings or only
with 1 small yellow or milky white markings at apical-lateral angle .............................. 4
-Median carina of frons only basal /4 distinct; clypeus with 1 grayish white transverse marking basally
(Chou et al. 1994: Fig. 1: F) ..................................................... C. fopingensis
4. Sc+R of tegmina fork near base; costal areas with ivory-yellow longitudinal band from near base
to near apex, long and broad (Fig. 1) ........................................................ 5
-Sc+R of tegmina fork at middle; costal areas with ivory-yellow longitudinal band from near
middle to near apex, short and narrow, and with 1 small ivory-yellow triangular marking
before this band ......................................................... .... C. asymmetries
5. The apical cells of tegmina banded with grayish white color (Distant 1916: Fig. 48)............... .C. indicus
-The apical cells of tegmina banded with red color. .................................................. 6
6. Clypeus with apex ivory-yellow (Fig. 2); tegmina with 1 small blackish brown marking
near apex of Scl (Fig. 1); body smaller (length including tegmina 3.8 mm) ............. C. maolanensis
-Clypeus purplish brown (Chou et al. 1994: Fig. 6: F); tegmina without blackish brown marking near
apex of Scl (Chou et al. 1994: Fig. 6: A); body larger (length including tegmina 6.9 mm) ..... C. jilinensis
7. The yellowish white transverse band of frons broad (more than /3 of frons); styles of aedeagus symmetrical ..... 8
-The yellowish white transverse band of frons narrow (only 1/5 of frons); styles of aedeagus asymmetrical
(Chou et al. 1994: Fig. 4: A, B) .................................................. C. sym metries
8. Frons with apical /3 yellowish white (Ishihara 1954: Fig. 16: 2); Sc+R of tegmina fork near basal 2/5,
costal areas with 1 small triangular marking before ivory-yellow longitudinal band
(Ishihara 1954: Fig. 16: 4); body dark brown ...................................... .. C. japonicus


Florida Entomologist 88(1)







Chen et al.: New species of Caristianus from China


-Frons with apical /2 yellowish white; Sc+R of tegmina fork near middle, costal areas without
small triangular markings before ivory-yellow longitudinal band; body purplish brown
or light purplish brown ........... ... ..................................... .......... 9
9. Styles of aedeagus with 1 larger tooth near apex; aedeagus with 5 or 6 teeth on each side
(Chou et al. 1994: Fig. 2: A ..................................................... C. ziyangensis
-Styles of aedeagus and aedeagus without teeth (Fennah 1956: Fig. 15: K) ........................ C. ulysses
10. Vertex longer in middle than broad at base about 1.9:1 (Fennah 1965: Fig. 65); tegmina with 4 short
longitudinal fuscous-piceous stripes at apical margin (Fennah 1965: Fig. 68); body of male light
yellowish brown, of female scarlet .............................................. C. cardinalis
-Vertex longer in middle than broad at base about 1.25-1.4:1 (Fig. 8); tegmina without short longitudinal
fuscous-piceous stripes at apical margin (Fig. 10); body blackish brown ........................... 11
11. Frons purplish black; costal areas of tegmina with 3 small white markings; apex of aedeagus
with 1 slender process on each side, directed laterad; styles of aedeagus as long as aedeagus,
with apices crossing each other (Chou et al. 1994: Fig. 5: A) .......................... C. nigripectus
-Frons with apical half milky white (Fig. 9); costal areas of tegmina with 1 large and 1 small marking,
ivory-yellow (Fig. 10); aedeagus with subapically 2 processes, directed basad; styles of aedeagus
shorter obviously than aedeagus, with apices diverging (Figs. 14-16) ......................... C. liaoi


Caristianus maolanensis Chen et Li sp. nov.
(Figs. 1-7)

Description. Body length (from apex of vertex
to tip of abdomen): male 2.4 mm; including teg-
men: male 3.8 mm; tegmen length: male 3.1 mm.
Vertex subrectangular (Fig. 1), longer in middle
than broad across base (1.3:1). Frons narrow tri-
angle, longer in middle line than broad (1.7:1),
median carina with apical 4/5 distinct (Fig. 2).
Rostrum long, surpassing trochanter of median
leg. Mesonotum longer than vertex and pronotum
together (1.6:1). Sc+R of tegmina fork near basal
/3. Post-tarsomeres with segment I longer than II
and III together (1.3:1).
Anal segment of male broad at base and nar-
row at apex, distal margin convex, notched at
middle. Pygofer with each lateral margin pro-
duced near middle in 1 twisted digitate process,
with 1 small tooth on its outer side (Figs. 3 and 4).
Medioventral process deeply bifid, each limb long
spine-like, diverging distally, with 1-2 small teeth
on each outer side near basal 13 (Fig. 4). Aedeagus
swelling at apex, lateral margin sinuate, with 7-8
small teeth on each side. In ventral view, aedea-
gus with 2 strong processes produced from apex,
directed ventrocephalad. Styles of aedeagus sym-
metrical, as long as aedeagus, diverging at middle
and closing to each other distally (Figs. 6 and 7).
Genital styles moderately expanding distad, sin-
uate on ventral and dorsal margin, with 2 simple
teeth near middle and apex of dorsal margin, one
slender, sinuate process originating from ventral
margin and directed dorsad (Fig. 5).
Vertex yellowish brown, except for two stripes
laterally, and 1 stripe on each side of median car-
ina distally brown. Frons blackish brown, except
for apical angle milky white and 5 spots on lateral
margin yellowish brown. Eyes blackish brown,
ocelli yellowish brown, marginally tinted with


red. Antenna blackish brown. Clypeus blackish
brown, except for apex ivory-yellow. Rostrum yel-
low, but apex blackish brown. Pronotum and me-
sonotum blackish brown, except for lateral
carinae and areas between them yellowish brown.
Tegmina infuscate, middle of costal area with 1
milky white longitudinal band, in which 1 small
brown spot near Sc; posterior margin of clavus
milky white, inside of second claval vein with 5
small milky white spots; with veins in this area
concolorous, except those veins of apical half of
tegmina red. Wings slightly tinged light brown,
with veins dark brown. Legs ivory-yellow. Abdo-
men blackish brown.
Er ....... ,*.. This new species is named after the
type locality, Maolan National Nature Reserve in
Guizhou Province.
Distribution. Southwest China (Guizhou).
Specimens examined. Holotype male, CHINA:
Guizhou, Maolan National Nature Reserve
(25040'N, 108005'E), 600 m, 24-X-1998 (X.-S.
Chen) (IEGU).
Remarks. This new species is similar to C.
asymmetries Chou et al., but differs from the lat-
ter in: smaller body; tegmina with Sc+R fork near
basal /3; veins of apical half red; apical half aede-
agus symmetry; genital styles with slender pro-
cess near base.

Caristianus liaoi Chen et Tsai sp. nov.
(Figs. 8-16)

Description. Body length (from apex of vertex
to tip of abdomen): male 2.2 mm, female 2.8 mm;
including tegmen: male 3.7 mm, female 4.7 mm;
tegmen length: male 3.0 mm, female 3.9 mm.
Vertex triangular, longer in middle than broad
across base (1.4:1), with median carina, posterior
margin slightly sinuate (Fig. 8). Frons broad tri-
angle, longer in middle line than broad (1.3:1),







Florida Entomologist 88(1)


W72


6i





6


Figs. 1-7. Caristianus maolanensis Chen et Li sp. nov. 1. male holotype, dorsal habitus; 2. frons and clypeus; 3.
pygofer and anal segment, left side; 4. pygofer, ventral view; 5. right genital style, lateral view; 6. aedeagus, lateral
view; 7. aedeagus, ventral view. Scale bars = 1 mm (Fig. 1); 0.5 mm (Fig. 2); 0.2 mm (Figs. 3-7).


median carina with apical 13 distinct (Fig. 9). Ros-
trum long, surpassing trochanter of median leg.
Mesonotum longer than vertex and pronotum to-
gether (1.5:1). Sc+R oftegmina forking near basal
2/5. Post-tarsomeres with I segment longer than
II and III together (1.2:1).
Anal segment of male broad at base and nar-
row at apex, distal margin concave roundly. Py-
gofer with each lateral margin produced near
middle into tooth (Figs. 11). Medioventral process
deeply bifid, each limb broad at base, acuate at
apex, diverging distally (Fig. 12). Aedeagus swell-
ing at apex, lateral margin slick, anterior margin
with groove. In ventral view, aedeagus with 2
strong processes produced from subapical mar-
gin, directed ventrocephalad. Styles of aedeagus
symmetrical, shorter than aedeagus, diverging
distally (Figs. 14-16). Genital styles moderately
expanding distad, sinuate on ventral margin,
with 2 large cone-shaped teeth near apex of dor-
sal margin (Fig. 13).
Vertex yellowish brown, except for 2 stripes
laterally, and a stripe on each side of median car-
ina distally brown (Fig. 8). Frons with basal half


blackish brown, apical half milky white and 5
spots on lateral margin yellowish brown. Eyes
reddish brown, ocelli yellowish brown. Antenna
blackish brown. Clypeus blackish brown, except
for basal margin ivory-yellow and apex yellowish
brown. Rostrum yellowish brown, but apex black-
ish brown. Pronotum and mesonotum blackish
brown, except for lateral carinae of pronotum yel-
lowish brown (Fig. 8). Tegmina infuscate, middle
of costal area with 1 large milky yellow marking
and 1 small milky yellow marking; posterior mar-
gin of clavus yellowish brown, inside of second
claval vein with 3 milky white spots; with veins in
this area concolorous (Fig. 10). Wings slightly
tinged light brown, with veins dark brown. Legs
yellowish brown. Abdomen blackish brown.
ErL td ... ...* i. This new species is named in honor
of Ms. Q.-R. Liao, collector of the type specimens.
Distribution. Southwest China (Guizhou).
Specimens examined. Holotype male, CHINA:
Guizhou, Maolan National Nature Reserve
(25040'N, 108005'E), 600 m, 25-X-1998 (Q.-R.
Liao) (IEGU). Paratype 3 females, same data as
holotype.


March 2005







Chen et al.: New species of Caristianus from China


1 1


Figs. 8-16. Caristianus liaoi Chen et Tsai sp. nov. 8. head and thorax, dorsal view; 9. frons and clypeus; 10. teg-
men; 11. pygofer and anal segment, left side; 12. medioventral process of pygofer; 13. right genital style, lateral
view; 14. aedeagus, ventral view; 15. aedeagus, dorsal view; 16. aedeagus, lateral view. Scale bars = 0.5 mm (Figs.
8-9); 1 mm (Fig. 10); 0.2 mm (Figs. 11-16).


Remarks. This species is similar to C. cardina-
lis Fennah, but differs from the latter in: vertex
shorter (longer in middle than broad across base
about 1.4x, not 1.9x); on tegmina, the base of cos-
tal cell without ivory yellow spots and the apical
cells without short longitudinal fuscous-piceous
stripes; pygofer with each lateral margin pro-
duced near middle in a tooth, not long process;
medioventral process deeply bifid; aedeagus with
two strong processes produced from subapical
margin, directed ventrocephalad.

ACKNOWLEDGMENTS
We thank Ms. Qi-Rong Liao, Institute of Entomol-
ogy, Guizhou University, Guiyang, Guizhou Province,
for collecting and donating specimens. We also thank
Mr. Hui-Ming Chen, Management of Maolan National
Natural Reserve, Libo County, Guizhou Province, for his
help in this study. This research was supported by the
Florida Agricultural Experiment Station and approved
for publication as Journal Series No. R-10478.

REFERENCES CITED
CHEN, D.-H., AND Y.-J. LIN. 2001. Caristianus indicus
Distant: a new record to China. Jiangxi Plant Pro-
tection 24(4): 116.


CHOU I, J.-S. LU, J. HUANG, AND S.-Z. WANG. 1985. Eco-
nomic Insect Fauna of China, Fasc. 36, Homoptera
Fulgoroidea. Science Press, Beijing, China. 152 pp.
CHOU I., F. YUAN, AND Y.-L. WANG. 1994. Descriptions
of the Chinese species of the genus Caristianus Dis-
tant (Homoptera: Achilidae). Entomotaxonomia
16(1): 38-50.
DISTANT, W. L. 1916. Rhynchota. Homoptera: Appen-
dix. The Fauna of British India, including Ceylon
and Burma 6: 1-248.
DLABOLA, J. 1957. Die Zikaden Afghanistans (Homopt.-
Auchenorrhynchal) nach den Ergebnissen der von
Herrn J. Klapperich in den Jahren 1952-1953 nach
Afghanistan unternommenen Expedition. Mitt.
Munch Ent. Ges., Munich 47: 265-303.
FENNAH, R. G. 1949. New exotic Fulgoroidea. Annals of
Natural History, or Magazine of Zoology, Botany and
Geology 2(12): 585-606.
FENNAH, R. G. 1950. A generic revision ofAchilidae (Ho-
moptera: Fulgoroidea) with descriptions of new spe-
cies. Bull. Brit. Mus. (Nat. Hist.) Ent. 1(1): 1-169.
FENNAH, R. G. 1956. Fulgoroidea from Southern China.
Proc. California Acad. Sci., Ser. 4 28(13): 441-527.
FENNAH, R. G. 1965. New Achilidae (Homoptera: Fulgor
oidea) from Central America, South Africa and
South East Asia. Zool. Beitr., Berlin (N.S.) 11: 77-
102.
ISHIHARA, T. 1954. Homoptera notes. Sci. Rep. Matsu-
yama Agric. College 14: 1-27.







Florida Entomologist 88(1)


March 2005


SYNONYMY OF TWO ARBOREAL TERMITES (ISOPTERA:
TERMITIDAE: NASUTITERMITINAE): NASUTITERMES CORNIGER
FROM THE NEOTROPICS AND N. POLYGYNUS FROM NEW GUINEA

RUDOLF H. SCHEFFRAHN1, JAN KRECEK1, ALLEN L. SZALANSKI2, JAMES W. AUSTIN2 AND YVES ROISIN3
'Fort Lauderdale Research and Education Center, University of Florida, Institute of Food and Agricultural Sciences
3205 College Ave., Fort Lauderdale, FL 33314

2Department of Entomology, University of Arkansas, Insect Genetics Research Laboratory, Fayetteville, AR 72701

3Behavioral and Evolutionary Ecology, CP 160/12, Universit6 Libre de Bruxelles
Av. F.D. Roosevelt 50, B-1050 Brussels, Belgium

ABSTRACT

Morphological examination of soldiers and images assigned to Nasutitermes polygynus from
New Guinea were determined to be conspecific with the neotropical species, N. corniger. A
portion of the mtDNA 16S rRNA gene was sequenced from nine N. corniger samples and
found to be congruent with that reported for N. polygynus. Complementary biological, behav-
ioral, chemical, and reproductive ecology data further support this synonymy. Nasutitermes
corniger was likely introduced to New Guinea as a result of accidental human transport.

Key Words: arboreal termites, taxonomy, distribution

RESUME

Se determine por medio de una examinaci6n morfol6gica de los soldados e images de Nasu-
titermes polygynus de Nueva Guinea que esta especie es conespecifica con la especie Neotro-
pical, N. corniger. Se determine que una porci6n de ADNmt 16S ARNr que fue secuenciada
de nueve muestras de N. corniger fue congruente con la porci6n de ADN conocida para N. po-
lygynus. Los datos biologicos complementarios, el comportamiento, ademas de la ecologia
quimica y reproductive apoyan esta sinonomia. Es probable que, Nasutitermes corniger fue
introducida al Nueva Guinea como resultado accidental del transport human.


Nasutitermes corniger (Motschulsky 1855) has
the broadest distribution of any neotropical ter-
mite species and is capable of establishment in
non-endemic localities (Scheffrahn et al. 2002). In
many places where N. corniger occurs, it is a dom-
inant species. Nasutitermes polygynus Roisin and
Pasteels 1985, is broadly distributed on the island
of New Guinea but is less common than other ar-
boreal nasutes from there (Roisin & Pasteels
1996).
In a molecular genetic analysis of Nasutiter-
mes from the tropical Pacific, Miura et al. (2000)
determined that N. polygynus and N. corniger are
sister species based on single mtDNA COII and
16S rRNA sequences from each species. Miura et
al. (2000) did not make morphological compari-
sons but noted remarkable similarities between
the two species. Because of the widespread range
of N. polygynus in New Guinea, Miura et al.
(2000) hypothesized that N. polygynus evolved
from an ancestral arrival ofN. corniger from the
New World. It was difficult, however, for the au-
thors to reconcile a natural trans-Pacific crossing,
thus inferring introduction by humans and a syn-
onymy ofN. polygynus and N. corniger.


In this paper we provide morphological, ge-
netic, behavioral, and chemical evidence that
N. polygynus is a synonym ofN. corniger.

MATERIALS AND METHODS

Morphological examinations are based on an
extensive collection of N. corniger from the New
World (Scheffrahn et al. 2005) and nine samples
from New Guinea. A synopsis of synonymy of
N. corniger is presented in Scheffrahn et al.
(2005) with the following additions:

Nasutitermes corniger (Motschulsky)

Nasutitermes polygynus Roisin and Pasteels
1985: [imago, Fig. 1; soldier Fig. 2. Type loc.:
Papua New Guinea, Nubia, 3 km on road to
Bunapas (Bogia District)]; Roisin & Pasteels
1996: 546-551 [imago, Fig. 40; soldier Fig. 41;
large worker, Figs. 42, 43; distribution, Fig. 44];
Roisin & Pasteels 1986: 149-167 [polycaly, polyg-
yny] Roisin & Pasteels (1985) described N. poly-
gynus from specimens collected in northeastern
Papua New Guinea. Additional soldiers from







Scheffrahn et al.: Synonymy of two Nasutitermes spp.


southeastern and southwestern Papua New
Guinea were measured in their redescription
(Roisin & Pasteels 1996) that also included photo-
graphs of the soldier, large worker mandible, and
large worker enteric valve armature.

Material Examined

All specimens are from Island of New Guinea
and were fixed in Bouin or FAA. TYPE COLONY
of N. polygynus, Nubia, Hansa Bay, Bogia Dis-
trict, 3 km on road to Bunapas, 16-XI-1978; J. M.
Pasteels (PNGT 4). Nubia, Hansa Bay, Bogia Dis-
trict, Sakula River bridge; Y. Roisin; 2-1-1984
(PNGT 508). Bunapas, Ramu River, Bogia Dis-
trict, behind airstrip; Y. Roisin; 23-VII-1984
(PNGT 751). Sisimangum, Hansa Bay, Bogia Dis-
trict; Y. Roisin; 8-IX-1984 (PNGT 827). Bogia, 12
km on road to Josephstaal, Bogia District; Y. Roi-
sin and J. M. Pasteels; 25-II-1985 (PNGT 900).
Gogol River valley, S. of Madang, 35 km from
main (coastal) road; Y. Roisin; 16-IX-1988 (PNGT
1274). Lake Murray, Western Province; Y. Roisin
and M. Leponce; 23-V-1990 (PNGT 1566). Nabire
(Irian Jaya); Y. Roisin; 12-XI-1995 (IRJT 3).
Kaimana (Irian Jaya), near airstrip; Y. Roisin; 21-
XI-1995 (IRJT 118).

Genetic Analysis

DNA was extracted from four Nasutitermes
ephratae (Holmgren), one N. guayanae (Holmgren),
one N. nigriceps (Haldeman), one N. rippertii
(Rambur), and nine N. corniger samples from the
Dominican Republic, Dominica, Nevis, Guade-
loupe, Puerto Rico, Mexico, Ecuador, Suriname,
and Jamaica per Szalanski et al. (2004). Polymer-
ase chain reaction (PCR) was conducted with the
primers LR-J-13007 (5'-TTACGCTGTTATC-
CCTAA-3') (Kambhampati & Smith 1995) and LR-
N-13398 (5'-CGCCTGTTTATCAAAAACAT-3') (Si-
mon et al., 1994). These PCR primers amplify an
approximately 428-bp region of the mtDNA 16S
rRNA gene. PCR reactions were conducted with 1
pl of the extracted DNA per Szalanski et al. (2000),
with a profile consisting of 35 cycles of 94C for 45
s, 46C for 45 s and 72C for 45 s. Amplified DNA
from individual termites was purified and concen-
trated on Microcon-PCR Filter Units (Millipore,
Bedford, MA). Samples were sent to University of
Arkansas Medical Sciences DNA Sequencing Core
Facility (Little Rock, AR) for direct sequencing in
both directions with an ABI Prism 377 DNA se-
quencer (Foster City, CA). GenBank accession
numbers for the Nasutitermes termites subjected
to DNA sequencing in this study are AY623085 to
AY623100. Consensus sequences for each sample
were obtained by using BioEdit 5.09 (Hall 1999).
The position of variable nucleotide sites among the
DNA sequences was obtained with MacClade v4
(Sinauer Associates, Sunderland, MA).


The distance matrix option of PAUP* 4.0b10
(Swofford 2001) was used to calculate genetic dis-
tances according to the Kimura 2-parameter
model (Kimura 1980) of sequence evolution. Mito-
chondrial DNA sequence of N. acajutlae
(Holmgren) (Kambhampati et al. 1996) was in-
cluded for phylogenetic analysis, along with
mtDNA 16S sequences for N. polygynus, N. trio-
diae (Froggatt), N. magnus (Froggatt), N. walker
(Hill), N. exitiosus (Hill), N. princeps (Desneux),
N. bikpelanus Roisin and Pasteels and N. pinoc-
chio Roisin and Pasteels from Miura et al. (2000).
Longipeditermes longipes (Haviland) and Hospi-
talitermes medioflavus (Holmgren) (Termitidae:
Nasutitermitinae) sequences from Miura et al.
(2000) were used as the outgroup taxa for the Na-
sutitermes dataset. DNA sequences were aligned
with CLUSTAL W (Thompson et al. 1994) and ad-
justed manually. Maximum likelihood and un-
weighted parsimony analysis on the alignments
were conducted by using PAUP* 4.0b10 (Swofford
2001). Gaps were treated as a fifth character
state. The reliability of trees was tested with a
bootstrap test (Felsenstein 1985). Parsimony
bootstrap analysis included 1,000 resamplings
with the Branch and Bound algorithm of PAUP*.
For maximum likelihood analysis, the default
likelihood parameter settings were used (HKY85
6-parameter model of nucleotide substitution,
empirical base frequencies) with the exception of
the transition/transversion ratio, which was set
to 1.357845:1. These parameters were used to
carry out a bootstrap analysis by either step-wise
addition or the maximum parsimony tree as the
starting tree.

RESULTS

Geographical Distribution

Nasutitermes corniger occurs over a north-
south distance of more than 6,000 km from south-
ern Mexico to northern Argentina, including the
West Indies, and much of the region except Chile,
Uruguay, and the Bahamas (Scheffrahn et al.
2005). There is one introduced population in
southeastern Florida (Scheffrahn et al. 2002) cur-
rently under an eradication program. The distri-
bution ofN. polygynus is given in Figure 1.

Morphology

Roisin & Pasteels (1985, 1996) reported some
variability in measurements as observed by
Scheffrahn et al. (2005), but character dimen-
sions ofN. corniger (Scheffrahn et al. 2005) from
the Neotropics and N. polygynus from New
Guinea (Roisin & Pasteels 1996) overlap for all 12
comparable measurements (7 images, 5 soldiers).
Coloration, pilosity, and fine structure for both
groups are also congruent (Fig. 2).







Florida Entomologist 88(1)


122$


i


-'s-~


Fig. 1. Collection sites (dark circles) ofNasutitermes corniger in New Guinea. Dark grey: elevation above 1000 m.


Genetic Analysis

The 428-bp region of the mtDNA 16S rRNA
gene was subjected to DNA sequencing from Na-
sutitermes corniger and 13 other Nasutitermes
taxa (Fig. 3). Among the nine N. corniger DNA se-
quences, 13 nucleotides were variable and genetic
diversity ranged from 0.0% between the Guade-
loupe and Nevis samples to 1.8% between the Ja-
maica and Nevis samples. To facilitate analysis
with the DNA sequences from Miura et al. (2000)
17 base pairs at the 5' end of our DNA sequences
were excluded for phylogenetic analysis. The
aligned DNA data matrix, which included 14 Na-
sutitermes taxa as well as the two outgroup taxa,
resulted in a total of 421 characters. Of these
characters, 111 (26%) were variable and 63 (15%)
were phylogenetically informative. This dataset
had only one most parsimonious tree (Fig. 4),
(length = 272, CI = 0.577), as documented using
the Branch and Bound search algorithm of
PAUP*. Bootstrap analysis of the aligned Nasuti-
termes taxa revealed that N corniger and N. eph-
ratae are monophyletic. Based on genetic distance
data, the N polygynus DNA sequence from Miura
et al. (2000) collected from New Guinea was most
similar to N. corniger from Mexico and Ecuador.
The consensus tree from the maximum likelihood
analysis (-In L = 1672.20365) was identical to the
maximum parsimony analysis.

DISCUSSION
The synonymy ofN. polygynus and N. corniger
is supported by morphological and genetic con-


gruency. Furthermore, Roisin & Pasteels (1986)
reported biological similarities forN. corniger and
N polygynus by virtue that both species are po-
lygynic and build polycalic (satellite) nests. Also
like N. corniger, Roisin & Pasteels (1996) report
crepuscular dispersal flights for N. polygynus fol-
lowing the first rains of the wet season.
Vrkoc et al. (1973) identified six monoterpenes
in the defensive secretion of N. costalis (=corni-
ger) from Cuba including the two major compo-
nents, terpinolene and limonene, found in N.
polygynus (Everaerts et al. 1988). The major
diterpenic components identified from the defen-
sive secretion of N. polygynus are trinervita-
1(15),8(19)-dien-2P,3a-diol and trinervita-
1(15),8(19)-dien-2P-ol (Dupont et al. 1981: Nasu-
titermes sp. B). Vrkoc et at. (1978) identified the
diol as the major diterpene component in the de-
fensive secretion ofN. corniger from Cuba. In the
four populations of N. corniger from Central
America analyzed by Gush et al. (1985), the diol is
also dominant, although sometimes partially re-
placed by its 2a,3a and 2a,3p-diol isomers,
whereas the latter constitutes 0.4-21.4% of the
diterpenic fraction.
We hypothesize that N. corniger was intro-
duced to New Guinea as a result of unintentional
human transport. This species was actually inter-
cepted several times in the U.S. and the U.K. in
plants from Central America or the West Indies
(Gay 1967). Established populations have been
introduced to Florida and Scotland (Scheffrahn et
al. 2002) and recent interceptions from Columbia
and Puerto Rico have been recorded, respectively,
in Clearwater and Jacksonville, Florida. We, like


e6


March 2005


d B


b
B






Scheffrahn et al.: Synonymy of two Nasutitermes spp. 31













*^-^^Hj"^-- BP


(/A
3


Fig. 2. Photomicrographs ofNasutitermes corniger. Lateral (A) and dorsal (C) views of soldier head capsule from
Irian Jaya, New Guinea. Lateral (B) and dorsal (D) views of soldier head capsule from Honduras. Dorsal (E) and
lateral (G) views of imago head capsule from Irian Jaya, New Guinea. Dorsal (F) and lateral (H) views of imago head
capsule from Venezuela.







Florida Entomologist 88(1)


March 2005


N. corniger Dominican Rep. DR164 100

N. corniqer Dominica DM69 093

68 N. corniger Nevis SKN218 097
N. corniger Guadeloupe GU118 099

8 N. corniger Jamaica JA90 096

N. corniqer Puerto Rico PR959 098

N. corniger Suriname SA14 095

N. corniger Coba Mexico 094

74 N. corniger Ecuador SA168 085

N. polygynus AB037343

N. ephratae Dominica DM 59 086

0 96 N. ephratae Tobago TT644 087

N. ephratae Belize BZ 15 088

N. ephratae Guadeloupe GU113 089

N. nigriceps Aruba NA14 090

N. guayanae Trinidad TT248 092

N. rippertii Bahamas BA2774 091

N. acajutlae Caribbean U50775
96
N. walker Australia AB037349
88
8884 N. triodiae Australia AB037347

N. magnus Australia AB037348

N. exitiosus Australia AB037350

_93 N. pinocchio Indonesia AB037353

N. bikpelanus P. New Guinea AB037352

N. princeps Indonesia AB037351

Longipeditermes longipes Malaysia AB037357

Hospitalitermes medioflavus Indonesia AB037358

Fig. 3. Single most parsimonious tree during a branch and bound search from PAUP* (Swofford 2001). Bootstrap
values for 1,000 replicates are listed above the branches supported at >50%. GenBank accession numbers for sam-
ples not sequenced in this study also are provided.



Miura et al. (2000), find it difficult to explain the transportation, (2) multiple recent introductions
widely separated localities (<1900 km, Fig. 2) of by ship or aircraft, or (3) a combination of both.
N. corniger on the island of New Guinea. We spec- The fact that N. corniger has not been reported
ulate that the New Guinea distribution is the re- from other islands in the southwestern Pacific re-
sult of (1) a single early maritime introduction gion suggests that introductions into this region
centuries ago from which the termites dispersed have been few, making the first hypothesis more
around New Guinea, possibly helped by human likely.







Scheffrahn et al.: Synonymy of two Nasutitermes spp.


ACKNOWLEDGMENTS

We thank Brian Cabrera and Michael Crosland, Fort
Lauderdale R.E.C., for their helpful reviews. Florida Agri-
cultural Experiment Station Journal Series No. R-10348.

REFERENCES CITED

DUPONT, A., J.-C. BRAEKMAN, D. DALOZE, J. M.
PASTEELS, AND B. TURSCH. 1981. Chemical composi-
tion of the frontal gland secretions from Neo-
Guinean nasute termite soldiers. Bull. Soc. Chim.
Belg. 90: 485-499.
EVERAERTS, C., J. M. PASTEELS, Y. ROISIN, AND O. BON-
NARD. 1988. The monoterpenoid fraction of the de-
fensive secretion in Nasutitermitinae from Papua
New Guinea. Biochem. Syst. Ecol. 16: 437-444.
FELSENSTEIN, J. 1985. Confidence limits on phyloge-
nies: An approach using the bootstrap. Evolution 39:
783-791.
GAY, F. J. 1967. A World Review of Introduced Species of
Termites. C.S.I.R.O. Australia, Melbourne, Bulletin
No. 286, 88 p.
GUSH, T. J., B. L. BENTLEY, G. D. PRESTWICH, AND B. L.
THORNE. 1985. Chemical variation in defensive se-
cretions of four species of Nasutitermes. Biochem.
Syst. Ecol. 13: 329-336.
HALL, T. A. 1999. BioEdit: a user-friendly biological se-
quence alignment editor and analysis program for
Windows 95/98/NT. Nucl. Acids Symp. Ser. 41: 95-98.
KAMBHAMPATI, S., AND P. T. SMITH. 1995. PCR primers
for the amplification of four insect mitochondrial
gene fragments. Insect Molec. Biol. 4: 233-236.
KAMBHAMPATI, S., K. M. KJER, AND B. L. THORNE. 1996.
Phylogenetic relationship among termite families
based on DNA sequence of mitochondrial 16S riboso-
mal RNA gene. Insect Mol. Biol. 5: 229-238.
KIMURA, M. 1980. A simple method for estimating evo-
lutionary rate of base substitutions through compar-
ative study of nucleotide sequences. J. Molec. Evol.
16: 111-120.
MIURA, T., Y. ROISIN, AND T. MATSUMOTA. 2000. Molec-
ular phylogeny and biogeography of the nasute ter-
mite genus Nasutitermes (Isoptera: Termitidae) in
the pacific tropics. Molec. Phylogenet. Evol. 17: 1-10.
MOTSCHULSKY, V. DE. 1855. Etudes entomologiques 4.
Hilsingfors, Imprim. Soc. Liter. Finnoise 8, 84 pp.
ROISIN, Y., AND J. M. PASTEELS. 1985. A new Nasutiter-
mes species from New Guinea (Isoptera: Termiti-
dae). Indo-Malayan Zool. 2: 325-330.
ROISIN, Y., AND J. M. PASTEELS. 1986. Reproductive
mechanisms in termites: polycalism and polygyny in


Nasutitermes polygynus and N. costalis. Insect. Soc.
33: 149-167.
ROISIN, Y., AND J. M. PASTEELS. 1996. The nasute ter-
mites (Isoptera: Nasutitermitinae) of Papua New
Guinea. Invertebr. Taxon. 10: 507-616.
SCHEFFRAHN, R. H., J. KRECEK, A. L. SZALANSKI, AND J.
W. AUSTIN. 2005. Synonymy of the neotropical ar-
boreal termites, Nasutitermes corniger and N. cos-
talis (Isoptera: Termitidae: Nasutitermitinae),
with evidence from morphology, genetics, and bio-
geography. Ann. Entomol. Soc. America 98: (in
press).
SCHEFFRAHN, R. H., B. J. CABRERA, W. H. KERN, JR.,
AND N-Y. SU. 2002. Nasutitermes costalis (Isoptera:
Termitidae) in Florida: first record of a non-endemic
establishment by a higher termite. Florida Entomol.
85: 273-275.
SIMON, C., F. FRATI, A. BECKENBACH, B. CRESPI, H. LIU,
AND P. FLOOK. 1994. Evolution, weighting, and phy-
logenetic utility of mitochondrial gene sequences
and a compilation of conserved polymerase chain re-
action primers. Ann. Entomol. Soc. America 87: 651-
701.
SWOFFORD, D. L. 2001. PAUP*: Phylogenetic analysis
using parsimony (*and other methods), ver. 4.0b10.
Sinauer, Sunderland, MA.
SZALANSKI, A. L., R. H. SCHEFFRAHN, J. W. AUSTIN,
J. KRECEK, AND N-Y. SU. 2004. Molecular phylogeny
and biogeography of Heterotermes (Isoptera: Rhino-
termitidae) in the West Indies. Ann. Entomol. Soc.
America (in press).
SZALANSKI, A. L., D. S. SIKES, R. BISCHOF, AND
M. FRITZ. 2000. Population genetics and phylogenet-
ics of the endangered American burying beetle,
Nicrophorus americanus (Coleoptera: Silphidae).
Ann. Entomol. Soc. America 93: 589-594.
THOMPSON, J. D., D. G. HIGGINS, AND T. J. GIBSON.
1994. CLUSTAL W: improving the sensitivity of pro-
gressive multiples sequence alignments through se-
quence weighting, position-specific gap penalties
and weight matrix choice. Nucleic Acids Res. 22:
4673-4680.
VRKOC, J., M. BUDESINSKY, AND P. SEDMERA. 1978.
Structure of 2a,3a-dihydroxy- and 2a,3p-dihydroxy-
1(15),8(19)-trinervitadienes from Nasutitermes cos-
talis (Holmgren). Coll. Czechoslovak Chem. Com-
mun. 43: 2478-2485
VRKOC, J., K. UBIK, L. DOLEJS, AND I. HRDY. 1973. On
the chemical composition of frontal gland secretion
in termites of the genus Nasutitermes (N. costalis
and N. rippertii; Isoptera). Acta Entomol. Bohemo-
slovaca 70: 74-80.







Florida Entomologist 88(1)


March 2005


TWO NEW SPECIES OF THE GENUS CAMPTOLOMA
(LEPIDOPTERA: NOCTUIDAE) FROM CHINA

MIN WANG AND Guo-HUA HUANG
Laboratory of Insect Ecology, South China Agricultural University, Guangzhou, Guangdong 510642, P.R. China

ABSTRACT

Two colorful medium-sized moths, Camptoloma kishidai sp. nov. and C. bella sp. nov., from
South China, are described and illustrated. C. kishidai can be recognized from the related
species C. carum Kishida, from Taiwan by the reddish yellow-ground color on the forewing
upperside, the tornal area without an irregular red pink patch, and by antemedian and post-
median fasciae connected at their lower ends by a longitudinal fascia. C. bella is distin-
guished from the allied species C. interiorata (Walker) by the characteristics of a reddish
patch, and discocellular, antemedian and postmedian fasciae. A key to the species of the ge-
nus is supplied. All the type specimens are deposited in the Laboratory of Insect Ecology,
South China Agricultural University.

Key Words: Taxonomy, Noctuidae, Shimentai Nature Reserve, Cengwanglaoshan Nature
Reserve

RESUME

Dos mariposas nocturnas de colorido aspect y median tamano Camptoloma kishidai sp.
nov. y C. bella sp. nov. del sur de China son descritas e ilustradas. Se puede reconocer
C. kishidai de C. carum Kishida, una especie cercana de Taiwan por el color amarillo-rojiso
de la parte superior del ala anterior, el area tornal no present la mancha irregular de color
rojo-rosado, y por las fasciae antemedianos y posteromedianos que se conectan al los termi-
nos basales por una fascia longitudinal. Se distingue C. bella de C. interiorata (Walker), una
especie aliada, por las caracteristicas de la mancha roja, y por el discocelular y las fasciae an-
temediana y posteromediana. Se provee una clave de las species del g6nero Camptoloma.
Todos los especimenes tipo estan depositados en el Laboratorio de Ecologia de Insectos, de
la Universidad Agricola del Sur de China.


As a part of biodiversity conservation for sus-
tainable development, an inventory of biodiver-
sity is important, particularly in the areas of
tropical and subtropical regions that housed such
numbers of species. In comparison with higher
plants and larger animals, the inventory of in-
sects is still fragmentary and incomplete. South
China, within the Indo-Australian Region, is one
of the major sites of biodiversity in China. In or-
der to appeal public awareness and to develop
conservation measures in this region, we started
the inventory work on macrolepidoptera, includ-
ing butterflies and larger moths, at selected sites.
Recently, we conducted a macrolepidoptera
survey in Shimentai Nature Reserve, Guangdong
Province and Cenwanglaoshan Nature Reserve,
Guangxi Province. We found two species of the ge-
nus Camptoloma new to science. Here we give the
descriptions, along with a key to the genus.
The genus Camptoloma consists of medium
sized, colorful moths and was established by
Felder (1874), with Camptoloma erythropygum its
type species. It is closely related to the genus Leu-
copardus Hampson (1894) and forms a natural
group with the latter (Kishida, 1984). Recently,
the genus Leucopardus Hampson has been consid-
ered a synonym of the genus Camptoloma Felder


by Holloway (1988), who moved the genus to the
family Noctuidae from the family Arctiidae based
on anatomical characters. In this paper, we regard
Camptoloma and Leucopardus to be separated
genera in agreement with some other authors
(Kishida 1984; Zolotuhin 2000) due to the differ-
ences in the wing pattern, although male genitalia
of the two genera are closely related in structure.
Currently, five species of the genus Campto-
loma have been documented: C. interiorata
(Walker [1865]) from China, Japan, Korea and
the Russian Far East; C. binotatum Butler, 1881,
from N. India and Assam, Nepal, Myanmar, and
S. China; C. carum Kishida, 1984, from Taiwan;
C. vanata Fang, 1994, from Jiangxi and Hainan of
China, N. Vietnam, and C. mangpua Zolotuhin &
Witt, 2000, from Sikkim.

MATERIALS AND METHODS

Specimens were collected by light traps during
the field surveys conducted in Cenwanglaoshan
and Shimentai Nature Reserves. The type speci-
mens are deposited in South China Agricultural
University (SCAU).
Photographs of specimens were taken with a
Nikon Coolpix995, along with a Leica MZ125 for







Wang & Huang: New Species of Camptoloma


genitalia figures. Digital images were imported
into Adobe Photoshop 5.0 for labeling and plate
composition.

Camptoloma kishidai sp. nov. (Fig. 1)

Female

Wing expanse 37 mm, length of forewing 18
mm, antenna length 9 mm. Head comparatively
small; frons covered with yellow scales, subequal
to the breadth of eyes; labial palpi uniformly or-
ange yellow, rather short, coated with long scales
and sparse bristles ventrally; eyes dark brown,
naked; antenna filiform, dark gray except for a
darker part at distal /. Thorax yellow, with dorsal
median and lateral brown streaks, the former one
rather slimmer; legs yellow except for dorsal fe-
mura, inner tibiae and tarsi dark brown. Abdo-
men orange-yellow with crimson end.
Forewing nearly triangular, costa with basal /3
prominently arched, termen and dorsum with
mid-part curved outwardly, apex pointed and tor-
nus nearly rounded; hindwing almost rounded,
costa straight. Forewing ground color reddish-
orange with dark brown fasciae and spots, which
is consisting of antemedian, discocellar, post-
median, submarginal and a longitudinal fascia
placed on the lower basal wing, and two dark
brown spots on the lower termen near tornus.
Antemedian, postmedian and discocellular
fasciae distinct and well defined, the former two
straight, nearly parallel to each other, and with
their lower ends connected by a longitudinal dark
fascia; discocellular fascia short, curved inwardly,
placed nearer to antemedian fascia than to post-
median fascia; submarginal fascia obsolete, trace-
able; longitudinal fascia on the lower basal wing
straight and with its distal end nearly arriving
the lower part of antemedian fascia; marginal fas-
cia and tornal reddish patch that represented in
other Camptoloma species completely untrace-
able; cilia orange red. Hindwing ground color


Fig. 1. Camptoloma kishidai sp. nov.: Female, holo-
type, upperside.


light orange-red, without marking, cilia orange.
Underside of both wings uniformly orange-yellow.
Male. Unknown.
Holotype: Female, Shimentai Nature Reserve,
400m altitude, 2428'N, 11323'E, Yingde County,
Guangdong Province, China, 18-IV-2003, leg.
Guo-Hua Huang.
Paratype 1 female, same data as holotype.
Etymology: The name of the species is named
after Mr. Y. Kishida of Tokyo, who supplied us
with valuable references and suggestions.
Distribution: China (Guangdong Province).
Biology: The specimens were captured at night
by light trapping, although there is a record of
species in the related genus Leucopardus Hamp-
son being taken flying by day (Holloway, 1988).
The new species is readily recognized from
other members in the genus Camptoloma by the
reddish-yellow forewing ground color, tornal area
concolorous with the ground color, without reddish
patch represented in some other related species,
antemedian and postmedian fasciae connected at
their lower ends by a longitudinal fascia.

Camptoloma bella sp. nov. (Figs. 2-4)

Male

Wing expanse 45 mm, length of forewing 23
mm, antenna length 7.5 mm. Head comparatively
small; frons covered with yellow scales, with up-
per portion a little gray, slightly broader than the
breadth of eyes; labial palpi yellow, rather short,
coated with long scales and sparse bristles ven-
trally; legs yellow, apart from tibiae and tarsi
black outwardly; eyes dark brown, naked; an-
tenna filiform, black with white intersegmental
rings. Thorax yellow with dorsal median and lat-
eral brown streaks. Abdomen orange yellow.
Forewing triangular, somewhat longer, costa
slightly arched, termen nearly straight, dorsum
slightly curved, apex pointed, tornus near
rounded. Hindwing nearly rounded, costa
straight. Forewing ground color yellow, with typi-
cal Camptoloma wing pattern. Antemedian, post-
median, disocellular, submarginal and marginal
fasciae dark brown and well defined, the former
two fasciae slant from costa to tornal red patch,
gradually narrowed to their lower ends. Discocel-
lular fascia fine, placed nearer to postmedian fas-
cia than to antemeddian fascia, with its lower
part gradually shaded to the end of postmedian
fascia. Submarginal fascia slightly curved in-
wardly, marginal fascia straight. The two longitu-
dinal fasciae placed on the lower basal wing
straight, well defined and nearly extending to the
reddish patch; the two dark brown spots on lower
termen much larger and well developed; the red-
dish patch in tornal area much smaller. Hindwing
ground color yellow, without distinct marking.
Cilia yellowish-white.







Florida Entomologist 88(1)


Figs. 2-3. Camptoloma bella sp. nov.; 2. Male, holotype, upperside; 3, Female, Paratype, upperside.


Male genitalia. Tegumen broad, uncus slim
with pointed end, saccus short, rod-like, valva
long, strongly constricted medially, costa narrow
with a kidney-like costal lobe; cucullus densely
coated with fragile spines; juxta with long lateral
extension; aedeagus with well developed cornuti.
Female. Wing expanse 45 mm, length of fore-
wing 23.5 mm, antenna length 8.5 mm. Similar
to male in wing pattern, but wings are slightly
broader, abdomen with distal end concolorous.
Holotype: Male, Cengwanglaoshan Nature Re-
serve, 1200 m altitude, 2435'N, 10640'E, Tianlin
County, Guangxi Province, China, 28-V-2002, leg.
Min Wang.
Paratype: 1 Female, same data as holotype.
Etymology: The name of the species, bella, is
come from its colorful wing pattern.
Distribution: China (Guangxi Province).
The new species is related to C. binotata Butler
in appearance, but the characteristics of reddish


Fig. 4. Male genitalia of Camptoloma bella sp. nov.


patch, discocellular, antemedian and postmedian
fasciae make it unmistakable.

DISCUSSION

Members in the genus Camptoloma have a
similar forewing pattern, the typical pattern
incl. yellowish ground color with dark brown
fasciae, including five transverse fasciae (e.g.,
antemedian, discocellular, postmedian, sub-
marginal and marginal fasciae), and two longi-
tudinal brown fasciae on the lower basal wings;
a reddish patch at tornal region; black spots in
cilia located at lower part of the termen; hind-
wing ground color uniform, without any mark-
ing.
The development or absence of the above
mentioned characters supply useful diagnoses
for different species. The most distinguished
species in the genus is C. kishidai, which has
the reddish ground color, with complete reduc-
tion of the reddish patch at tornal region that is
commonly represented in other species. The sec-
ond readily identified species is C. vanata
among the remaining species with yellowish
ground color, by its complete absence of most
dark brown fasciae including antemedian, post-
median, submarginal and marginal fasciae. The
third one is C. carum from Tawain with its sub-
marginal fascia obsolete and marginal fascia
absent.
The next four, C. interiorata, C. binotata, C.
mangpua, and C. bella had typical Camptoloma
wing patterns with all the fasciae and reddish
patch presented. The easily recognized one is C.
mangpua for its ill-developed tornal angle and
curved antemedian fascia. C. interiorata is sep-
arated from the remaining ones by its finer and
nearly paralleled antemedian and postmedian
fasciae. C. binotata and C. bella are similar in ap-
pearance, but the discocellar fascia in C. bella is
placed more outwardly than that in C. binotata.


March 2005







Wang & Huang: New Species of Camptoloma


Moreover, the reddish patch is less developed China, reported as an important insect pest on
and the submarginal fascia is much broader in Quercus ssp., Sapium sebiferum et al. (Fang,
C. bella. 2000; Zheng 2001).
Though the economic importance of the two For the convenience of field identification, we
new species is uncertain, there is one species of present a key to the known species of the genus
the genus, Camptoloma interiorata Walker in NE. Camptoloma as follows:


KEY TO SPECIES OF THE GENUS Camptoloma FIELDER, 1874

1. Forewing ground color reddish-yellow ......................................... C. kishidai sp. nov.
Forewing ground color yellow .................................................................. 2
2. Forewing upperside with submarginal fascia absent ............................................... 3
Forewing upperside with submarginal fascia present ............................................... .4
3. Forewing upperside with antemedian and postmedian fasciae present. ......................... C. carum
Forewing upperside without antemedian and postmedian fasciae .............................. C. vanata
4. Forewing narrow without distinct anal angle, antemedian fascia with middle part curved
outw ardly ....................................................... ............. C. m angpua
Forewing broader with distinct anal angle, antemedian fascia straight, or not curved outwardly ........... 5
5. Forewing upperside with discocellular bar much nearer to postmedian fascia that to
antemedian fascia .......................................................... C. bella sp. nov.
Forewing upperside with discocellular bar not as above stated ....................................... .6
6. Forewing upperside with postmedian fascia much broader than submarginal fascia ........... C. binotatum
Forewing upperside with postmedian and submarginal fascia similar in breadth .............. C. interiorata


ACKNOWLEDGMENTS

We are grateful to Mr. Y. Kishida for constructive
criticism of the manuscript, as well as to Dr. M. Owada
and Mr. K. Yazaki, all in Tokyo for offering valuable ar-
ticles. For the field survey, we are indebted to Mr. Guo-
Zhong Xie, Mr. Ling-Sheng Huang, of Shimentai Nature
Reserve, and Mr. Yao Pan of Cenwanglaoshan Nature
Reserve, for their kind assistance. This study was partly
supported by Pro Natura Foundation-Japan and Na-
ture Conservation Society of Japan.

REFERENCES CITED
FANG, C. L. 2000. Faunna Sinica, Insecta Vol. 19 (Lepi-
doptera, Arctiidae). Science Press, Beijing. pp. 312-
315.


HAMPSON, E. E. 1894. The fauna of British India, in-
cluding Ceylon and Burma. Taylor and Francis, Lon-
don. pp. 31-32.
HEPPNER, J. B., AND H. INOUE. 1992. Lepidoptera of Tai-
wan 1(2): Checklist. Assoc. Trop. Lepid., Gainesville.
p. 187
HOLLOWAY, J. D. 1988. The moths of Borneo. Part 6.
Kuala Lumpur: Malay. Nat. Soc., pp. 74-76.
KISHIDA, Y. 1984. A new species of the genus Campto-
loma from Taiwan (Lepidoptera, Arctiidae). Tinea 11
(25): 207-209.
ZHENG, W. Y. 2001. Biological characteristics of Camp-
toloma interiorata Walker. Forestry Science and
Technology 26(4): 22-25.
ZOLOTUHIN, V. V., AND T. J. WITT. 2000. The Camptolo-
minae of Vietnam and adjacent territories (Lepidop-
tera, Noctuidae). Entomofauna (Suppl.) 11 (1): 1-12.







Florida Entomologist 88(1)


March 2005


BODY WEIGHTS AND EGG LOADS IN FIELD-COLLECTED
PODISUS MACULIVENTRIS (HETEROPTERA: PENTATOMIDAE)

JESUSA CRISOSTOMO LEGASPI AND BENJAMIN C. LEGASPI, JR.1
USDA-ARS-CMAVE, FAMU-Center for Biological Control, 6383 Mahan Drive, Tallahassee, FL 32308
'Employed by State of Florida, contact through senior author.

ABSTRACT

Body weights and egg loads of field populations of the spined soldier bug, Podisus maculiven-
tris (Say) (Heteroptera: Pentatomidae) were studied from grape vineyards in Florida from
April to November, 2003. Two main generation peaks were found in June and September.
Mean female body weight throughout the year was similar to those obtained in various crops
in Indiana. In both studies, body weights were comparable to those found in laboratory ex-
periments where females were fed 1 prey item every 3 to 9 days. Egg loads in Florida were
similar to those found in field populations in Indiana. The increase in numbers of immature
eggs later in the Florida season may be an indication of continued egg production in older fe-
males. We interpret this as possible evidence of synovigeny in the field. This result is consis-
tent with previous laboratory data showing that immature eggs are continuously produced
throughout female lifetime. Larger females predictably had higher mean egg loads. The sim-
ilarity in biological characteristics found in field populations in Indiana and Florida suggest
that the predator has similar impacts on pest species by low feeding rates.

Key Words: ovigeny, predator, grape, vineyard, pheromone

RESUME

El peso del cuerpo y la carga de los huevos de poblaciones del chinche, Podisus maculiuentris
(Say) (Heteroptera: Pentatomidae), fueron estudiados en vifias en la Florida desde abril hasta
noviembre de 2003. Se encontr6 dos picos en las generaciones principles en junio y septiembre.
El promedio del peso del cuerpo de las hembras atrav6z del afio fue similar al obtenido de hem-
bras en various cultivos en Indiana. En ambos studios, el peso del cuerpo fue comparable al ob-
tenido de los experiments de laboratorio donde las hembras fueron alimentadas con 1 unidad
de presa cada 3 a 9 dias. La carga de huevos en la Florida fue similar a las encontradas en po-
blaciones de campo en Indiana. El aumento en el numero de huevos inmaduros mas tarde du-
rante la estaci6n en Florida puede ser una indicaci6n de la producci6n continue por parte de
hembras mas viejas. Nosotros interpretamos este como evidencia possible de sinovogenia (la pro-
ducci6n de huevos atrav6z de la vida de la hembra) en el campo. Este resultado es consistent
con los datos del laboratorio previous demostrando que los huevos inmaduros continuamente pro-
ducidos durante la vida de la hembra. Como esperamos, las hembras mas grandes tenian un pro-
medio mayor de carga de huevos. La similitud en las caracteristicas biol6gicas encontradas en
las poblaciones en el campo en Indiana y Florida sugiere que el depredador tiene un impact si-
milar sobre las species de plagas por las tasas bajas en alimentaci6n.


The spined soldier bug, Podisus maculiventris
(Say) (Heteroptera: Pentatomidae), is found
throughout North America and known to feed on
>75 species of insect prey, primarily immature
Coleoptera and Lepidoptera (McPherson 1980).
Because the predator also plays a role in natural
control of key pests and is available as a commer-
cial control agent, much is known about its biol-
ogy under laboratory conditions (e.g., Drummond
et al. 1984; Legaspi & O'Neil 1993a, b, 1994;
Wiedenmann & O'Neil 1991). In contrast, rela-
tively few studies have investigated P maculiven-
tris in the field (see Evans 1982; O'Neil 1988;
Wiedenmann & O'Neil 1992).
In field-cage experiments, the estimated at-
tack rate of P maculiventris on the Mexican bean
beetle, Epilachna varivestis Mulsant (Coleoptera:
Coccinellidae) was =0.5 per day at low (sub-eco-


nomic) prey densities of <10 prey/m2 crop leaf
area (Wiedenmann & O'Neil 1992; O'Neil 1997).
At higher densities of =10-42 prey/m2, represent-
ing economic pest levels, maximal attack rates
were =2 per day. In spite of such low attack rates,
P maculiventris is able to persist in a variety of
cropping systems through several adaptive mech-
anisms. Under conditions of food scarcity, P mac-
uliventris maintains longevity, but reduces its
fecundity (Legaspi & O'Neil 1993a; Legaspi & Le-
gaspi 1998). Starvation causes an increase in lev-
els of lipid, which the predator uses as energy
reserves (Legaspi & O'Neil 1994). Body mass also
declines (O'Neil & Wiedenmann 1990; Legaspi &
O'Neil 1993b). Furthermore, the predator may
enhance its survival through phytophagy to pro-
vide water and possibly carbohydrates (Wieden-
mann et al. 1996).







Legaspi & Legaspi: Field-Collected Podisus maculiventris


Legaspi et al. (1996) compared body weights,
egg loads and lipid levels in female P maculiven-
tris collected in alfalfa, potato, soybeans, and fal-
low fields in Indiana from 1987 to 1989 against
laboratory individuals under controlled feeding
regimens. Field populations showed levels of
these parameters comparable to laboratory speci-
mens provided 1 prey item every 3-9 d, thus sup-
porting the earlier finding of low field predation
rates (Wiedenmann & O'Neil 1992). Further-
more, body lipid levels were higher during the
drought year of 1988, suggesting conservation of
energy reserves, as documented in the laboratory
(Legaspi & Legaspi 1998). In this study, we com-
pared body weights and egg loads in maculiven-
tris collected by pheromone traps in Florida
muscadine grape vineyards in 2003 against labo-
ratory females under known feeding regimens.

MATERIALS AND METHODS

From April 17 to November 14, 2003, P macu-
liventris were collected from the FAMU-Center for
Viticulture muscadine grape vineyard about 10
miles east of campus in Tallahassee, Florida (Leon
County). Sampling methods were similar to those
described in Legaspi et al. (2004). A glass vial filled
with pheromone mixture (Aldrich 1988) and a cot-
ton wick, as well as a vial of water inserted with a
cotton wick, were placed inside each plastic covered
trap. The trap was made from an inverted plastic
food container. Insects entered through a wire
screen funnel at the top and were removed through
the screw cap lid at the bottom. The pheromone
mixture and water were replaced bi-weekly or as
needed. From April 17 to June 23, 11 traps were
used (14 cm diameter x 24 cm height). The number
of traps used was increased to 16 from June 24 to
July 9 (14 cm diameter x 19 cm height), and to 27
from July 10 to November 14, 2004 (15 cm diame-
ter x 21 cm height). Field collections were made
mainly around 3:00 p.m., when most adults were
observed to be caught. Samples were collected
daily except the weekends. Some P maculiventris
adults were observed to feed on prey such as
glassy-winged sharpshooter, flies, and spiders.
Adult P maculiventris collected from the traps
were weighed individually in the laboratory on a
Mettler PB 3002 analytical balance (Mettler To-
ledo, Hightstown, NJ) with a precision of +0.0001 g.
All adults were kept in an ultra-low freezer at
-80C (Revco Model ULT 1786-3-A36, Kendro
Laboratory Products, Asheville, NC) until dissec-
tions of female adults were done to measure the
numbers of eggs in the ovaries. Methods of dissec-
tion and egg load measurements follow methods
described in Legaspi et al. (2004). The dorsal and
ventral abdominal body walls of the females were
separated and the numbers of eggs in the ovaries
were counted. Eggs were classified as mature
(bigger, dark-colored, rough texture, and chorion


prominent) and immature (light-colored, smooth
texture, chorion not prominent).

Statistical Analysis
Linear regressions on egg loads and female
body weights were performed with Systat (Systat
Software, Inc., Point Richmond, CA).

RESULTS AND DISCUSSION

Because the numbers of pheromone traps used
increased during the season, numbers of predators
sampled are presented as insects per trap (Fig. 1).
The field population of P maculiventris appeared
to show two main peaks. The first, and more prom-
inent peak was observed in June, followed by a less
pronounced population peak in September. The
two peaks probably correspond to two generations
during the season. Adults that hibernated start
field activity in March to April, and population
numbers peak in June. The second peak in Sep-
tember indicates the second field generation.
Average body weights of female P. maculiven-
tris were relatively constant during the sampling
period (Fig. 2). Body weights are displayed to-
gether with four lines showing comparative
weights of females reared in the laboratory under

4 A. Number Females per Trap





2





-tJ
S Apr Jun Aug Oct Dec
4 4
B: Number Males per Trap

3 -


2 -






Apr Jun Aug Oct Dec
Sampling Date (2003)

Fig. 1. Numbers of Podisus maculiventris collected
per pheromone-baited trap (x SE) in muscadine grape
vineyard, Leon Co., FL.







Florida Entomologist 88(1)


A: Weights Female Podisus macutventns


At
4 M

a4-
. i' 1"~~? i J '' ~^


My Jur Jul Aug


SUp Oc0


0.
B Sa-ploe Sc





MAr HI Jwn Jul Aug S" Oc
Samprlg Dale (2003)

Fig. 2. Weights (mg) of female Podisus maculiventris
(x SE) in grapes. A) Four lines indicate estimated
mean laboratory weights of P. maculiventris in cultures
fed ad libitum, and 1 prey item at intervals of 1, 3, and
9 days (Legaspi et al. 1996); B) Sample size obtained at
sampling date, Leon Co., FL.


known feeding regiments. Legaspi et al. (1996)
estimated that adult, unmated P maculiventris
females fed ad libitum (0 days between meals),
and 1 prey item every 1-, 3-, and 5-days would
weigh an estimated mean of 80.9, 79.3, 76.1, and
66.6 mg, respectively. These lines are superim-
posed on the field data. With few exceptions be-
tween 3- and 9-day feeding lines, the vast
majority of the field population weighed less than
the benchmark level of 66.6 mg, indicating low
field predation rates. The present results are com-
parable to those obtained by Legaspi et al. (1996)
for P maculiventris in various crop systems in In-
diana where female body weights were similar to
laboratory females reared on a feeding regimen of
1 prey item every 3 to 9 days. Legaspi et al. (2004)
used the same procedure to study field popula-
tions of P maculiventris collected by pheromone
traps from May to August 2003 in a muscadine
grape vineyard at the Florida A&M University
Center for Viticulture in Tallahassee, Florida.
Field-collected females were found to have live
body weights comparable to females fed less than
one prey item every 9 days in the laboratory.
Body weights of males are shown for compari-
son (Fig. 3), although no similar studies have
been performed on the effects of feeding regimens
on body weights in the laboratory. Male body
weights are known to be less than those of fe-
males under both laboratory and field conditions
(Legaspi et al. 1996). These studies support the
finding of low field predation rates in Podisus


A: Weights Male Podisus maculiventris









I t f


20 B: Sample Size


z 5 -


0.111
Apr May Jun Ju Aug Sep
Sampling Date (2003)

Fig. 3. Weights of male Podisus maculiventris (mg,
x SE) in grapes, 2003, Leon Co., FL.


maculiventris (Wiedenmann & O'Neil 1992; and
others).
Egg load dissections during the season are
shown for mature, immature, and total eggs (Fig.
4). The numbers of immature eggs (Fig. 4b) indi-
cate low numbers early in the season, followed by
a subsequent increase, possibly due to ovigenesis
in the field population. Insects that produce eggs
after emergence are termed "synovigenic". The
terminology was originally developed for para-
sitic Hymenoptera, but is applicable to other in-
sects (Jervis & Kidd 1996; Jervis et al. 2001),
although it had not been studied in predators pre-
vious to Legaspi & Legaspi (2004) (M. Jervis,
Univ. Cardiff, personal communication). Recent
laboratory data suggest that P. maculiventris is
strongly synovigenic (Legaspi & Legaspi 2004).
The present study may be interpreted as evidence
for synovigeny in a field population of P macu-
liventris. However, this conclusion is made with
caution because of the presence of females with-
out eggs (Fig. 4) and because the ages and individ-
ual histories of the specimens are unknown.
Legaspi & O'Neil (1994) determined that labo-
ratory females with egg loads >25 corresponded to
15-d-old predators fed ad libitum to 1 prey item
every 3 days. Conversely, predators with <25 eggs
corresponded to 15-d-old females fed 1 prey item
at intervals >3 days. Mean egg load of 25 was used
as a benchmark by Legaspi et al. (1996) to charac-
terize field populations and is superimposed on
field egg loads in Fig. 4c. With the exception of a


March 2005







Legaspi & Legaspi: Field-Collected Podisus maculiventris


25 A: Mature eggs
20





0 -
25
20 B: Immature Eggs
L 15
10
Z 5



30 C. Total Eggs
25 -
20 -


15-

40 -
D: Sample Size
30-
z 20 I
10 I

Apr May Jun Jul Aug Sep Oct Nov
Sampling Date (2003)

Fig. 4. Mean egg loads of female Podisus maculiven-
tris (mg, x SE) in grapes. A) Mature eggs; B) Imma-
ture eggs, showing increasing numbers later in the
season; C) Total eggs, line indicates 25 eggs which is the
egg load of laboratory females fed 1 prey item every 3
days (Legaspi et al. 1996); D) Sample size obtained at
sampling date, 2003, Leon Co., FL.


single observation, all egg loads were found below
the benchmark line, possibly indicating low field
predation rates. The sample sizes upon which all
egg counts were based roughly correspond to the
June and September peaks found for the field pop-
ulation (Figs. 4c and 1). Unlike body weights, it is
more difficult to make inferences based on mean
egg loads because of the confounding effects of
feeding regimen and predator age. Age tends to
increase egg load; food scarcity to decrease it.
Both factors are largely unmeasured in our field
populations. Legaspi & O'Neil (1994) also con-
cluded that P maculiventris exhibits continued
egg development and storage until deposition,
thereby suggesting a synovigenic predator.
Linear regressions of egg loads on female body
weights gave the expected result that larger fe-
males had higher total numbers of mature and
immature eggs (Fig. 5) (TOTAL EGGS = -10.92 +
0.277 WEIGHT; F = 170.9; df= 1, 580; P < 0.01; R2


Egg Load and Female Body Weight


20 40 60 80 100 120


Female Weight (mg)

Fig. 5. Total egg load as a function of female body
weight (mg). Line indicates linear regression: TOTAL
EGGS = -10.92 + 0.277 WEIGHT (P < 0.01).


= 0.23). Regressions on numbers of mature eggs
(MATURE = -9.2 + 0.23 WEIGHT), and immature
eggs (IMMATURE = -1.79 + 0.045 WEIGHT;)
were similarly significant (F = 145.1; df = 1, 577;
P < 0.01; R2 = 0.2; and F = 38.1; df = 1, 577; P <
0.01; R2 = 0.06, respectively). The positive rela-
tionship we found between egg loads and female
body weights has been amply documented. Jervis
& Kidd (1996) cite numerous examples in the lit-
erature of positive relationships between female
body size or weight and the following measures of
reproduction: ovariole number (two references);
egg load (18 references); and lifetime fecundity
(nine references).
In conclusion, P maculiventris probably has
two field generations in Florida, which are not dis-
crete due to the largely mild year-long climate and
absence of severe winters. Mean female body
weight in the field was similar to those obtained in
various crops in Indiana, indicating low predation
rates in both cases. Egg loads of field-collected fe-
males were comparable to those found in Indiana.
The increase in numbers of immature eggs later
in the season may be an indication of continued
egg production in older females. This finding is ex-
pected given previous laboratory data showing
that immature eggs are continuously produced
throughout female lifetime. Larger females pre-
dictably had higher mean egg loads. The similar-
ity in biological characteristics found in field
populations of Indiana and Florida suggest that P
maculiventris plays similar roles in the suppres-
sion of pest insects by feeding on prey in low rates,
despite the differences in crop and climate.

ACKNOWLEDGMENTS

We thank Ignacio Baez (USDA, ARS, CMAVE,
FAMU-CBC) and Mohamed Soumare (FAMU-CBC) for











technical assistance. Florida A&M University under-
graduate students, Jeffory Head and Elizabeth Ani-
nakwa, assisted in field and laboratory sampling. We
also thank FAMU-Center for Viticulture and Small
Fruits for use of the vineyards. Helpful reviews on the
manuscript were provided by Dr. Alfredo Lorenzo, Dr.
Michael Hubbard (Florida A&M University, Tallahas-
see, FL), and two anonymous reviewers.
The use of trade, firm, or corporation names in this
publication does not constitute an official endorsement
or approval by USDA or ARS of any product or service to
the exclusion of others that may be suitable.

REFERENCES CITED

ALDRICH, J. R. 1988. Chemistry and biological activity
of pentatomid sex pheromones, pp. 417-431 In H. G.
Cutler [ed.], Biologically Active Natural Products:
Potential Use in Agriculture. American Chemical So-
ciety, Washington, D.C.
DRUMMOND, F. A., R. L. JAMES, R. A. CASAGRANDE, AND
H. FAUBERT. 1984. Development and survival of Po-
disus maculiventris (Say) (Hemiptera: Pentatomidae),
a predator of the Colorado Potato Beetle (Coleoptera:
Chrysomelidae). Environ. Entomol. 13: 1283-1286.
EVANS, E. W. 1982. Consequences of body size for fecun-
dity in the predatory stinkbug, Podisus maculiven-
tris (Hemiptera: Pentatomidae). Ann. Entomol. Soc.
Am. 75: 418-420.
JERVIS, M. A., AND N. A. C. KIDD. 1996. Insect Natural
Enemies: Practical Approaches to Their Study and
Evaluation. Chapman & Hall, London.
JERVIS, M. A., G. E. HEIMPEL, P. N. FERNS, J. A. HAR-
VEY, AND N. A. C. KIDD. 2001. Life-history strategies
in parasitoid wasps: a comparative analysis of 'ovig-
eny'. J. Anim. Ecol. 70: 442-458.
LEGASPI, J. C., AND B. C. LEGASPI, JR. 1998. Life history
trade-offs in insects, with emphasis on Podisus mac-
uliventris (Heteroptera: Pentatomidae), pp. 71-87 In
M. Coll and J. R. Ruberson [eds.], Predatory Het-
eroptera: Their Ecology and Use in Biological Con-
trol. Thomas Say Publications in Entomology. ESA,
Lanham, MD.
LEGASPI, J. C., AND B. C. LEGASPI, JR. 2004. Does a
polyphagous predator prefer prey species that confer
reproductive advantage?: Case study of Podisus ma-
culiventris. Environ. Entomol. 33: 1401-1409.
LEGASPI, J. C., AND R. J. OTNEIL. 1993a. Life history of
Podisus maculiventris given low numbers of Epi-


March 2005


lachna varivestis as prey. Environ. Entomol. 22:
1192-1200.
LEGASPI, J. C., AND R. J. O'NEIL. 1993b. Fat body re-
serves of predators fed low inputs of prey. Environ.
Entomol. 23: 1254-1259.
LEGASPI, J. C., AND R. J. O'NEIL. 1994. Lipids and egg
production of Podisus maculiventris (Heteroptera:
Pentatomidae) under low rates of predation. Envi-
ron. Entomol. 12: 1254-1259.
LEGASPI, J. C., R. J. O'NEIL, AND B. C. LEGASPI, JR.
1996. Trade-offs in body weights, egg loads, and fat
reserves of field-collected Podisus maculiventris
(Heteroptera: Pentatomidae). Environ. Entomol. 25:
155-164.
LEGASPI, J. C., J. P. SHAPIRO, AND B. C. LEGASPI, JR.
2004. Biochemical comparison of field and labora-
tory populations of Podisus maculiventris (Het-
eroptera: Pentatomidae) in Florida. Southwest.
Entomol. 29: 301-303.
MCPHERSON, J. E. 1980. A list of the prey species of Po-
disus maculiventris (Hemiptera: Pentatomidae). Gt.
Lakes Entomol. 13: 18-24.
O'NEIL, R. J. 1988. Predation by Podisus maculiventris
(Say) on Mexican bean beetle (Epilachna varivestis
Mulsant) in Indiana soybeans. Can. Entomol. 120:
161-166.
O'NEIL, R. J. 1997. Functional response and search
strategy of Podisus maculiventris (Heteroptera: Pen-
tatomidae) attacking Colorado Potato Beetle (Cole-
optera: Chrysomelidae). Environ. Entomol. 26: 1183-
1190.
O'NEIL, R. J., AND R. N. WIEDENMANN. 1990. Body
weight of Podisus maculiventris (Say) under various
feeding regimens. Can. Entomol. 122: 285-294.
WIEDENMANN, R. N., AND R. J. O'NEIL. 1991. Searching
behavior and time budgets of the predator Podisus
maculiventris. Entomol. Exp. Appl. 60: 83-93.
WIEDENMANN, R. N., AND R. J. O'NEIL. 1992. Searching
strategy of the predator Podisus maculiventris (Say)
(Heteroptera: Pentatomidae). Environ. Entomol. 21:
1-9.
WIEDENMANN, R. N., J. C. LEGASPI, AND R. J. O'NEIL.
1996. Impact of prey density and facultative plant
feeding on the life history of the predator Podisus
maculiventris (Heteroptera: Pentatomidae), pp. 95-
119 In O. Alomar and R. N. Wiedenmann [eds.], Zoo-
phytophagous Heteroptera: Implications for Life
History and Integrated Pest Management. Thomas
Say Publications in Entomology. ESA, Lanham, MD.


Florida Entomologist 88(1)







Myartseva & Ruiz-Cancino: New Coccophagus from Mexico


NEW SPECIES OF COCCOPHAGUS WITH DENSELY SETOSE AXILLA
FROM MEXICO (HYMENOPTERA: APHELINIDAE)

SVETLANA N. MYARTSEVA AND ENRIQUE RUIZ-CANCINO
Division de Estudios de Postgrado e Investigaci6n, U.A.M. Agronomia y Ciencias
Universidad Aut6noma de Tamaulipas, Ciudad Victoria, 87149, Tamaulipas, M6xico

ABSTRACT

Two new species of the genus Coccophagus from Mexico, neocomperei sp. nov. and debachi
sp. nov. are described and illustrated. The redini species-group is proposed for the genus
Coccophagus, based on three species with unusual station on the axillae. A key to identify
both sexes of members of the redini group is provided.

Key Words: Mexico, Hymenoptera, Aphelinidae, Coccophagus, new species

RESUME

Se described e ilustran dos species nuevas del g6nero Coccophagus de M6xico, neocomperei
y debachi. Se propone el grupo de species redini para el g6nero Coccophagus, basado en tres
species con una disposici6n inusual de setas en las axilas. Se incluye una clave para la iden-
tificaci6n de ambos sexos de los miembros del grupo redini.


Translation provided by author.


Coccophagus Westwood is one of the largest
genera in the family Aphelinidae. Species of this
genus are endoparasitoids of Coccoidea, mainly
soft scales (Coccidae), and rarely mealybugs
(Pseudococcidae). Males are generally hyperpara-
sitoids on primary parasitoids, including conspe-
cific females. Species of Coccophagus have been
used successfully in biological control of pestifer-
ous soft scales worldwide (Clausen 1978; Rosen &
De Bach 1991). Over 200 species have been de-
scribed worldwide. Sixty species are known to oc-
cur in the New World, including 39 species
distributed in the Neotropics and 32 species dis-
tributed in the Nearctic region (Woolley 1997;
Noyes 2002). Ten species are known to occur in
Mexico (Myartseva & Ruiz-Cancino 2000; Noyes
2002; Myartseva & Coronado-Blanco 2003). Most
of the species from the New World were described
by H. Compere and L. O. Howard.
Two new species of Coccophagus are described
in this article, both with unusual station of the
axilla. Only one species, Coccophagus redini Gi-
rault, with densely setose axillae was previously
known. Girault (1924) described this species from
one female collected in Australia, and it was later
redescribed by Compere (1931). Abbreviations for
depositories of the material examined: BNMH-
Natural History Museum, London, U.K.; UAT-
Universidad Aut6noma de Tamaulipas, Ciudad
Victoria, Tamaulipas, Mexico; UCRC-University
of California, Riverside, California, USA; USNM-
National Museum of Natural History, Washington,
D.C., USA.; ZISP-Zoological Institute of Academy
of Sciences, Saint Petersburg, Russia.


Coccophagus neocomperei
Myartseva & Ruiz, sp. nov. (Figs. 1-8)

Description

FEMALE. Length: 0.90-1.10 mm.

Coloration

Head light yellow, frontovertex yellow, occiput
with black oval spots along foramen, antenna
club and last two funicular segments very slightly
infuscate. Mesosoma light yellow, pronotum black
medially, mesoscutum with black anterior mar-
gin, outline of axillae black, propodeum black, on
sides brownish-yellow (female from Campeche
with white longitudinal stripe behind spiracle).
Legs light yellow. Wings hyaline, venation of fore
wing very slightly infuscate. Endophragma black.
Metasoma whitish-yellow, third to seventh terg-
ites black dorsally, ovipositor sheaths black.

Morphology

Head wider than mesosoma, slightly wider
than high and less than 2x wider than length. Fr-
ontovertex slightly longer than wide, its width less
than half of head width. Occipital margin straight.
Ocelli in slightly obtuse triangle; hind ocelli sub-
equal in distance from eyes and occipital margin.
Eyes slightly more than 2x as long as cheeks. Man-
dible (Fig. 1) with one tooth and a broad dorsal
truncation. Labial and maxillary palpi one- and
two-segmented, respectively. Clypeus as in Fig. 2.






Florida Entomologist 88(1)


2









11


Figs. 1-8. Coccophagus neocomperei, sp. nov., female: 1-mandible, 2-clypeus, 3-antenna, 4-axilla, 5-stig-
mal vein, 6-middle tarsus and tibial spur, 7-ovipositor; male: 8-antenna.


March 2005







Myartseva & Ruiz-Cancino: New Coccophagus from Mexico


Antennae (Fig. 3) inserted lower than lower level
of eyes. Distance between toruli very slightly
longer than distance from torulus to eye. Radicula
about 2x as long as wide. Scape slightly more than
4.5x as long as wide. Pedicel about 2x as long as
wide. First funicular segment the longest, 3.7x as
long as wide and 1.4x longer than pedicel. 2nd-3rd
segments subequal in length, each 1.6-1.7x as long
as wide. Club about 2x as long as wide and sub-
equal in length to last two funicular segments
combined. First funicular segment without sen-
silla, others with 2-3 sensilla each.
Mesoscutum wider than long. Midlobe of me-
soscutum densely setose, each side lobe with 3
long setae, axillae (Fig. 4) with one long and 8-13
short setae. Scutellum shorter than mesoscutum,
wider than long, with 3 pairs of long setae, 3rd
pair the longest. Propodeum with short triangu-
lar prominence medially. Endophragma widely
rounded on apex. Fore wing about 2.5x as long as
wide, marginal fringe short, disk with thinner
and shorter setae along apical margin (0.06x
length of wing). Submarginal vein with 8 long se-
tae, marginal vein about 1.7x longer than sub-
marginal and with 8-10 long setae on lower
margin. Stigmal vein as in Fig. 5. Hind wing
about 4.5x as long as wide, marginal fringe about
0.3 of maximal width of wing; disk station very
short and thin. Midtibial spur (Fig. 6) slightly
longer than basitarsus, which is shorter than re-
maining tarsal segments combined. Ovipositor
(Fig. 7) about 0.7x as long as middle tibia; third
valvula 0.2x as long as second valvifer.

MALE. Length: 0.8 mm.

Coloration

Similar to female, but head with frontovertex
orange-yellow, antennae whitish-yellow and
without infuscations, midlobe of mesoscutum
blackish posteriorly, axillae and notauli black,
scutellum blackish on posterior margin and some-
times on anterior margin also. Propodeum black,
with white longitudinal curved stripe behind spi-
racle or more often with one white spot under spi-
racle. Hind coxae blackish near base.

Morphology

Frontovertex as long as wide, its width about
half of head width. Ocelli larger and in more ob-
tuse triangle. Eyes about 1.4x longer than cheeks.
Antennae (Fig. 8) inserted at the level of lower
margin of eyes. Scape about 3.7x as long as wide.
Pedicel subtriangular, 1.3x wider than length.
First funicular segment the longest and slightly
swollen, about 2x as long as wide and 0.7x as long
as scape. 2nd segment slightly shorter and about
2x as long as wide, 3rd segment 0.8x as long as
second and about 1.5x as long as wide. Club 4x as


long as wide and longer than the last two funicu-
lar segments combined. All funicular and claval
segments with many sensillae, situated on 1st
segment in 2-3 rows, on 2nd in 1-2 rows, on 3rd-
6th in one row. Axillae with reticulate sculpture
and with one long and 5-7 short setae. Fore wing
2x as long as wide. Basitarsus of middle leg sub-
equal to the next two tarsal segments combined.
Genitalia 0.4x as long as middle tibia.
Comments. Coccophagus neocomperei sp. nov.
is similar to the Australian species Coccophagus
redini Girault, the only other species with
densely setose axillae, but it can be easily distin-
guished from this species by characters given in
the key (see below).
Etymology. This new species in named in
honor of chalcidologist Harold Compere who
worked in the University of California, Riverside,
USA, and described many species of Coccopha-
gus, and authored the first species revision ofCoc-
cophagus of the world.
Material examined. Holotype: Female, reared
from soft scale on Leucaena sp., Mexico, Guerrero,
Acapulco, 12-VI-2000, S. N. Myartseva. Paratypes:
16 females, 3 males (card mount), 3 females, 4
males (slide mount), same date as holotype;
Campeche, Cd. del Carmen, one female on card, 30-
VII-1984 (G. Gordh) (UCRC, No. 54587); Veracruz,
85 km. S of Veracruz, 180-200 m, one male on card,
31-VII-1984 (G. Gordh) (UCRC, No. 54596).
Specimen deposition. Holotype (mounted on
slide) and paratypes, one female from Campeche,
one male from Veracruz, 6 females and one male
from Guerrero (on cards) deposited in UCRC; 5
paratype females and one paratype male (on
cards) deposited in USNM; 2 paratype females
and 2 paratype males (on slides) deposited in
BMNH; 5 paratype females and one paratype
male (on cards) deposited in ZISP; one paratype
female and 2 paratype males (on slides) deposited
in UAT.

Coccophagus debachi
Myartseva & Ruiz, sp. nov. (Figs. 9-12)

FEMALE. Length: 1.20-1.40 mm.

Coloration

Body coloration is very similar to Coccophagus
neocomperei sp. nov., but occiput without black
oval spots along foramen, mesoscutum entirely
light yellow, propodeum black with white longitu-
dinal straight stripe behind spiracle on each side
and metasoma with 4 to 6th tergites black dor-
sally

Morphology

Head slightly wider than mesosoma and its
own height and about 2x as wide as long. Fron-







Florida Entomologist 88(1)


Figs. 9-13. Coccophagus debachi sp. nov., female: 9-antenna, 10-stigmal vein, 11-ovipositor; male:12-an-
tenna. Coccophagus redini, female: 13-antenna (redrawn from Compere, 1931).


March 2005







Myartseva & Ruiz-Cancino: New Coccophagus from Mexico


tovertex slightly wider than long, its width about
half of head width. Ocelli in about rectangle trian-
gle; hind ocelli separated from occipital margin by
distance slightly longer than diameter of one ocel-
lus and from eye margin by slightly longer dis-
tance. Eyes about 1.5x as long as cheeks.
Mandible and clypeus as in C. neocomperei. An-
tennal scape (Fig. 9) 5x as long as wide. Pedicel 2x
as long as wide. First funicular segment 4x as
long as wide and 1.4x as long as pedicel. 2nd seg-
ment 0.7x as long as 1st and 2.5x as long as wide.
Third segment 0.8x as long as 2nd and 1.5x as
long as wide. Club about 2.5x as long as wide and
slightly longer than two last funicular segments
combined. First funicular segment without sen-
silla, others with 2-3 sensillae each. Axillae with
7-9 setae (one longer). Each side lobe with 3 long
setae. Scutellum shorter than mesoscutum, wider
than length, with 3 pairs of long setae. Propo-
deum with short triangular prominence medially.
Endophragma widely rounded on apex. Fore wing
2.4x as long as wide, disk with thinner and
shorter setae along apical margin (0.10 x length
of wing). Submarginal vein with 10 long setae,
marginal vein about 1.5x longer than submar-
ginal vein and with 10 long setae on lower mar-
gin. Stigmal vein as in Fig. 10. Hind wing about
4.5x as long as wide, marginal fringe about 0.3x of
maximal width of wing; disk station very short
and thin. Midtibial spur slightly longer than basi-
tarsus, which is subequal in length to all remain-
ing tarsal segments combined. Ovipositor (Fig.
11) slightly exserted, 0.9x as long as middle tibia;
third valvula 0.7x as long as second valvifer.

MALE. Length: 1.10-1.20 mm.

Coloration

Similar to female, but frontovertex yellow, oc-
ciput with black oval spots along foramen, anten-
nae whitish-yellow and without infuscation,
midlobe of mesoscutum widely blackish distad,
scutellum blackish basally and apically. Hind
coxae blackish. Metasoma with 3rd-7th tergites
black dorsally.

Morphology

Frontovertex slightly wider than long, its
width slightly more than half of head width.
Ocelli larger than in female and in obtuse trian-
gle; hind ocelli separated from eye margin by dis-
tance of diameter of one ocellus and slightly
longer than that from occipital margin. Eyes 2.7x
as long as cheeks. Antennae (Fig. 12) inserted at
the level of lower margin of eyes. Scape 3.4x as
long as wide. Pedicel about 1.6x wider than long.
First funicular segment the longest, swollen,
about 2x as long as wide and 1.3x as long as scape,
2nd segment shorter and also 2x as long as wide.


3rd segment 0.8x as long as second and slightly
less than 2x as long as wide. Club 3.6x as long as
wide and shorter than the last two funicular seg-
ments combined. All flagellar segments with
many sensillae. Axillae with reticulate sculpture
and with 7-8 setae (one longer). Fore wing about
2.4x as long as wide, disk station as in female.
Submarginal vein with 9 long setae. Marginal
vein longer than submarginal. Midtibial spur
slightly longer than basitarsus, which is subequal
in length to next three tarsal segments combined.
Genitalia 0.6x as long as middle tibia.
Comments. Coccophagus debachi, sp. nov. is
similar in coloration and morphology to the new
Mexican species C. neocomperei. Females of both
species can be distinguished by the following char-
acters: C. debachi has occiput pale yellow, third
gastral tergite pale yellow, propodeum with white
longitudinal straight stripe behind spiracle on
each side, second funicular segment 2.5x as long
as wide, third segment 0.8x as long as the second,
club about 2.5x as long as wide, ovipositor 0.9x as
long as middle tibia, and third valvula 0.7x as long
as second valvifer (Fig. 11). Coccophagus neocom-
perei has occciput with black elongate spot on
sides of foramen, third gastral tergite black dor-
sally, propodeum brownish-yellow on sides, second
funicular segment 1.7x as long as wide, third seg-
ment subequal to the second, club about 2x as long
as wide, ovipositor 0.7x as long as middle tibia,
and third valvula 0.2x as long as second valvifer
(Fig. 7). Males of both species can be distinguished
by the following characters: C. debachi has the
first funicular segment longer than scape, second
to fifth flagellar segments decreasing in length
distally (Fig. 12) and genitalia 0.6x as long as mid-
dle tibia, whereas C. neocomperei has the first fu-
nicular segment shorter than scape, second to fifth
flagellar segments subequal in length (Fig. 8), and
genitalia 0.4x as long as middle tibia.
Etymology. This species is named in honor of
American entomologist Paul De Bach, who col-
lected this new species in Mexico. His material for
our study was loaned from the Entomological Re-
search Museum, University of California, River-
side, USA, including specimens: NN 54579-
54580, 54582-54586, 54588-54591, 54593-54595.
Material examined. Holotype: Female, col-
lected in pan trap, Mexico, Baja California Sur,
Las Barracas, ca. 30 km E of Santiago, 20-IV-1984
(coll. P. De Bach) (No. 54583), deposited in UCRC.
Paratypes (same data as the holotype) are depos-
ited: one female on slide, 23-IV-1984 (No. 54588),
two females on cards, 5-II-1984 (No. 54585), 20-
IV-1985 (No. 54582) and one male on card, 30-IV-
1985 (No. 54590), one male on slide, 1-VI-1985
(No. 54592) (all UCRC); two females on cards, 4-
VI-1985 (No. 54584), 15-VI-1985 (No. 54586) and
one male on card, 27-V-1986 (No. 54591)-in
USNM; one female and one male on cards, 21-IV-
1986 (No.54589, 12-VI-1986 (No. 54594)-in







Florida Entomologist 88(1)


BMNH; one female and one male on cards, 5-V-
1986 (No. 54579), 12-VI-1986 (No. 54595)-in
ZISP; one female and one male on cards, 5-V-1986
(No.54580), 1-VI-1985 (No.54593)-in UAT.

DISCUSSION

According to Compere (1931), Annecke and In-
sley (1994), and Hayat (1998), seven species-
groups are recognized in the genus Coccophagus:
lycimnia, ochraceus, malthusi, pseudococci,
tschirchii, varius, and zebratus-groups. We pro-
pose a new species-group, the redini-group, for
three species: C. redini Girault, 1924 from Austra-


lia and the two new species from Mexico described
herein, C. neocomperei and C. debachi. Species of
this group differ from other known species-groups
mainly by their unusual axillae, which are
densely setose, including one longer seta. Species
in the redini-group are similar to those of the
ochraceus-group in that the funicle segments have
excentric articulations, propodeum with median
triangular prominence, stigmal vein swollen, body
bicolored; but in species of the redini-group, fe-
males have the first funicular segment without
sensillae, fore wing apically with thinner and
shorter setae, and males have the first funicular
segment swollen, curved and the largest.


KEY TO THE SPECIES OF COCCOPHAGUS OF THE REDINI-GROUP

1. Fem ales ................... .............................................................. 2
- M ales ................... ................................................................ 4
2. Pronotum entirely black, gaster entirely blackish. First funicular segment with sensilla
(Fig. 13) .................................................................. redini Girault
-Pronotum and gaster partly pale yellow. First funicular segment without sensilla (Figs. 3, 9) ............... 3
3. Occiput pale yellow. 3rd gastral tergite pale yellow. Propodeum with white longitudinal
straight stripe behind spiracle on each side. 2nd funicular segment 2.5x as long as wide,
3rd segment 0.8x as long as 2nd. Club about 2.5x as long as wide. Ovipositor 0.9x as long
as middle tibia, third valvula 0.7x as long as second valvifer (Fig. 11) ................ debachi sp. nov.
-Occiput with black elongate spot on sides of foramen. 3rd gastral tergite black dorsally.
Propodeum brownish-yellow on sides. 2nd funicular segment 1.7x as long as wide,
3rd segment subequal to 2nd. Club about 2x as long as wide. Ovipositor 0.7x as long
as middle tibia, third valvula 0.2x as long as second valvifer (Fig. 7) ............. neocomperei sp. nov.
4. First funicular segment longer than scape. 2nd-5th flagellar segments decreasing in length
distally (Fig. 12). Genitalia 0.6x as long as middle tibia ............................ debachi sp. nov.
-First funicular segment shorter than scape. 2nd-5th flagellar segments subequal in length
(Fig. 8). Genitalia 0.4x as long as middle tibia ............................... neocomperei sp. nov.


ACKNOWLEDGMENTS

The authors thank Dr. S. V. Triapitsyn (Entomologi-
cal Research Museum, Department of Entomology, Uni-
versity of California, Riverside, California, USA) for the
loan of material, and Universidad Aut6noma de
Tamaulipas, Ciudad Victoria, Tamaulipas, M6xico,
CONACYT (M6xico) for financial support of this work,
and two reviewers and the Florida Entomologist Associ-
ate Editor on Systematics for valuable comments.

REFERENCES CITED

ANNECKE, D. P., AND H. P. INSLEY. 1974. The species of
Coccophagus Westwood, 1833 from the Ethiopian
region (Hymenoptera: Aphelinidae). Entomology
Memoir, Department of Agricultural Technical Ser-
vices, Republic of South Africa, No. 37: 1-62.
CLAUSEN, C. P. (Ed.). 1978. Introduced Parasites and
Predators ofArthropod Pests and Weeds. A world re-
view. USDA Agricultural Handbook 480. 545 pp.
COMPERE, H. 1931. A revision of the species of Cocco-
phagus, a genus of hymenopterous, coccid-inhabit-
ing parasites. Proc. U.S. Nat. Mus. 78: 1-132.


GIRAULT, A. A. 1924. Homo perniciosus and new Hy-
menoptera. Priv. Publ. 4 pp.
HAYAT, M. 1998. Aphelinidae of India (Hymenoptera:
Chalcidoidea): A Taxonomic Revision. Memoirs on
Entomology, International, 13. 416 pp.
MYARTSEVA, S. N., AND E. RUIZ-CANCINO. 2000. Anno-
tated checklist of the Aphelinidae (Hymenoptera:
Chalcidoidea) of Mexico. Folia Entomol6gica Mexi-
cana 109: 7-33.
MYARTSEVA, S. N., AND J. M. CORONADO-BLANCO. 2003.
Coccophagus rusti Compere: una especie de Africa
en M6xico. Entomologia Mexicana 2: 740-744.
NOYES, J. S. 2002. Taxapad 2002. Interactive Catalogue
of World Chalcidoidea 2001. CD.
ROSEN, D., AND P. DE BACH. 1991. Biological Control by
Natural Enemies. 2nd ed. Cambridge University
Press, London. 440 pp.
WOOLLEY, J. B. 1997. Aphelinidae, pp. 134-150 In G. A.
P. Gibson, J. T Huber, and J. B. Woolley [eds]. Anno-
tated Key to the Genera of Nearctic Chalcidoidea
(Hymenoptera). NRC Research Press. Ottawa, Can-
ada. 794 pp.


March 2005







Gonzalez et al.: Development of Dibrachys pelos


COMPARATIVE DEVELOPMENT AND COMPETITIVE ABILITY
OF DIBRACHYS PELOS (HYMENOPTERA: PTEROMALIDAE)
ON VARIOUS POTENTIAL HOSTS

JORGE M. GONZALEZ, ROBERT W. MATTHEWS AND JANICE R. MATTHEWS
Department of Entomology, University of Georgia, Athens, GA 30606

ABSTRACT

Dibrachys pelos (Grissell) is an occasional gregarious ectoparasitoid of Sceliphron caemen-
tarium (Drury). We report the second record of this host association, collected in western Ne-
braska, and present results of laboratory experiments on host suitability and utilization.
When D. pelos was reared alone on prepupae of 6 possible hosts, 4 proved entirely suitable:
the mud dauber wasps Sceliphron caementarium and Trypoxylon politum Say, and two of
their parasitoids, a velvet ant, Sphaeropthalma pensylvanica (Lepeletier) and a bee fly, An-
thrax sp. On these hosts D. pelos completed development in 2-4 weeks, with average clutch
sizes of 33-57, of which 24.7% were males. The other two hosts tested, the flesh fly Neobel-
lieria bullata (Parker) and the leaf-cutter bee Megachile rotundata (Say), proved marginal,
with very few adult progeny produced. When reared on these same 6 hosts with the addition
of a competing parasitoid, Melittobia digitata Dahms, D. pelos fared poorly, being the sole
offspring producer in at most 30% of the trials (onAnthrax hosts) and failing to prevail at all
on T politum hosts. Comparative data on host conversion efficiency indicated that M. digi-
tata was more efficient than D. pelos on every host except Anthrax.

Key Words: host conversion efficiency, interspecific competition, Melittobia digitata

RESUME

Dibrachys pelos (Grissell) es un ectoparasitoide gregario occasional de Sceliphron caementa-
rium (Drury). Reportamos el segundo registro de este parasitoide asociado al mencionado
hospedador, colectados en el oeste de Nebraska. Se presentan los resultados de experiments
de laboratorio acerca de la utilizaci6n y conveniencia de hospedadores por D. pelos. Al criarlo
sobre prepupas de seis posibles hospedadores, cuatro resultaron altamente convenientes: las
avispas de nidos de barro Sceliphron caementarium y Trypoxylon politum Say, asi como sus
parasitoides, la hormiga de terciopelo Sphaeropthalma pensylvanica (Lepeletier) y la mosca-
abeja Anthrax sp. D. pelos complete su desarrollo sobre estos hospedadores en 2-4 semanas,
con una descendencia promedio entire 33-57 individuos, de los cuales el 24.7% fueron machos.
Los otros dos hospedadores utilizados, la mosca Neobellieria bullata (Parker) y la abeja
Megachile rotundata (Say), fueron marginales en eficiencia, produciendo una progenie redu-
cida. Al agregar Melittobia digitata Dahms como competitor, en crias sobre estos mismos
hospedadores, D. pelos lo hizo pobremente, ganando, como maximo, solo en 30% de los en-
sayos (sobre Anthrax) y fallando totalmente sobre T politum. Datos comparatives sobre la
eficiencia de conversion del hospedador como unico productor de progenie mostr6 que M. dig-
itata fue mas eficiente que D. pelos sobre cada hospedador except sobre Anthrax sp.


Translation provided by the authors.


Mud dauber wasps (Hymenoptera: Sphecidae)
of the widely distributed genera Trypoxylon and
Sceliphron share a complex ecological web of in-
quilines that either parasitize them or use their
nests (Matthews 1997). Habits, prey, and in-
quilines are particularly well known for the organ
pipe mud dauber, Trypoxylon politum Say (Barber
& Matthews 1979; Brockmann & Grafen 1989;
Cross et al. 1975; Molumby 1995; Volkova et al.
1999) and the yellow-and-black mud dauber, Sce-
liphron caementarium (Drury) (Shafer 1949;
Hunt 1993).
In addition to heavy parasitism by Melittobia
(Hymenoptera: Eulophidae) wasps and sarcoph-


agid and bombylid flies, both mud dauber species
also have other parasitoids that are less com-
monly encountered (Matthews 1997a). One of the
latter is Dibrachys pelos Grissell (Hymenoptera:
Pteromalidae) (Fig. la), an ectoparasitoid appar-
ently distributed across North America (Grissell
1974) but infrequently collected. The only pub-
lished record of D. pelos as a member of the mud
dauber "community" is that of Grissell (1974). De-
spite an extensive survey of trap-nesting wasps
and bees and their inquilines (mainly from the
eastern United States), Krombein (1967) found
no associated Dibrachys species. In our own wide-
ranging collections of mud dauber nests east of







Florida Entomologist 88(1)


the Mississippi River and particularly in the
southeastern US over the last 20 years, we have
never before found D. pelos.
Grissell (1974) reared this species on prepupae
of S. caementarium and other hosts, but little is
known of its natural host preferences or possible
competition with other parasitoids. Elsewhere,
other Dibrachys species have been reported to
parasitize various families of Hymenoptera and
Diptera (Floate et al. 1999; Smith & Rutz 1991;
Urban & Eardley 1995; Whiteman & Landwer
2000), suggesting that D. pelos may be an oppor-
tunistic polyphagous parasitoid capable of attack-
ing a variety of host species.
Field collection of a Sceliphron caementarium
nest that was parasitized by D. pelos enabled us
to investigate the latter species' ability to parasit-
ize other potential hosts. In order to better under-
stand its apparent rarity as a parasitoid of mud
dauber wasps, we also staged interspecific compe-
tition studies with Melittobia digitata Dahms,
one of the most common parasitoids of mud
dauber wasps.

MATERIALS AND METHODS

Three cells of a Sceliphron caementarium nest
collected by RWM at Lake McConaughy, Keith
Co., Nebraska on June 21, 2003 contained pupae
and recently emerged adults of Dibrachys pelos.
These were brought to our laboratory at the Uni-
versity of Georgia, Athens, GA and reared for one
generation on S. caementarium prepupae.
To investigate relative suitability of additional
common potential hosts, individual 2-day-old
mated female progeny from this D. pelos culture
were placed on prepupae of 5 species known to be
acceptable hosts for M. digitata: T politum Say,
the leaf-cutter bee, Megachile rotundata Say (Hy-
menoptera: Megachilidae), the flesh fly Neobel-
lieria bullata Parker (Diptera: Sarcophagidae),
the velvet ant Sphaeropthalma pensylvanica (Le-
peletier) (Hymenoptera: Mutillidae), and a bee fly
Anthrax sp. (Diptera: Bombyliidae). The first 3
species have been routinely used as hosts in other
studies on M. digitata (Gonzalez & Matthews
2002; Silva-Torres & Matthews 2003) and are
available readily; the last 2 species are them-
selves parasitoids of T politum (Cross et al. 1975;
Matthews 1997a, b). Concurrently, parallel cul-
tures ofD. pelos were maintained on S. caementa-
rium. Ten replicates of each host species were
used in all experiments except for Sph. pensyl-
vanica, for which only 3 prepupae were available.
All cultures were maintained at 25C, 65% RH.
Development time, progeny production, sex ratio,
and host use (suitability) were recorded.
To investigate potential interspecific competi-
tive interactions, an additional 10 replicates were
concurrently established on each host (except
Sph. pennsylvanica due to limited availability).


For these we simultaneously placed one mated 2-
day-old female each ofD. pelos and M. digitata on
the host, and maintained these under the same
conditions as the other cultures. Outcomes of
these competition experiments were scored as
won (only D. pelos adults emerged), lost (only
M. digitata adults emerged), or coexistence
(adults of both parasitoids emerged). Number of
adult progeny emerging and their sex ratio, were
also recorded. We did not conduct a parallel series
of intraspecific competition experiments (2 fe-
males of D. pelos on each host).
As one indicator of the relative suitability of
the various hosts, host conversion efficiency val-
ues (analogous to feed conversion efficiencies for
poultry or pork) were calculated for both D. pelos
and M. digitata. To do this, samples of 10 males
and 10 females of each parasitoid species were in-
dividually weighed on a Mettler@ balance and the
average weight of a single female and male of
each species was determined. Ten individuals of
each of the various hosts were also weighed to ob-
tain an average host weight. The average number
of males and females reared from each host when
each of the parasitoids were alone was multiplied
by the individual wasp's average weight, this be-
ing apportioned according to the average sex ratio
obtained when reared alone on the respective
hosts. This value was then divided by the average
host weight and the result multiplied by 100 to
give a percent, the host conversion efficiency.

RESULTS AND DISCUSSION

Host Suitability and Development Time

Grissell (1974) reported that D. pelos laid eggs
on prepupae of Sceliphron, as well as Ancistro-
cerus and Euodynerus (Hymenoptera: Vespidae,
Eumeninae), and Megachile pacifica, but com-
pleted development only in the first 2 hosts. In
our experiments, D. pelos oviposited also on at
least some of all hosts offered (Table 1).
The most successful development occurred
with 4 taxonomically diverse but ecologically re-
lated species-the mud daubers S. caementarium
and T politum, and their parasitoids, the velvet
ant Sph. pensylvanica and the bee fly,Anthrax sp.
(Fig. Ic); all individuals (100%) of these host spe-
cies were parasitized successfully, as defined by
emergence of D. pelos adult progeny. Develop-
ment times on these 4 preferred hosts were quite
similar, requiring 1-3 days for eggs, 7-14 days for
larvae, and 7-12 days for pupae, with the total de-
velopment time ranging from 16-27 days. These
ranges for each developmental stage are consis-
tent with data forD. pelos on S. caementarium re-
ported by Grissell (1974).
Although some eggs were laid on Megachile ro-
tundata and N. bullata hosts, most immature
D. pelos perished, so that on average fewer than


March 2005







Gonzalez et al.: Development of Dibrachys pelos


Fig. 1. (a) Dibrachys pelos female on prepupa of S. caementarium; body length of adult female D. pelos = 3 mm;
(b) Eggs of M. digitata on abdomen of newly closed adult D. pelos; (c) Gregarious larvae of D. pelos feeding on An-
thrax sp. (Diptera: Bombyliidae); (d) Larva of M. digitata (arrow) feeding on larva ofD. pelos.


4 adults closed from these 2 hosts (Table 1).
Furthermore, the life cycle took significantly
longer to complete on these "marginal" hosts. For
example, whereas D. pelos started laying eggs on
most hosts within 24 hours, oviposition was de-
layed for up to 4 days on N. bullata. Development
was also strikingly slower on N. bullata at every
stage with the result that adults emerged only af-
ter 24 to 36 days, compared to 16-27 days on the
4 preferred hosts. Development was also some-
what slower on Megachile, requiring from 19-31
days. Grissell (1974) attempted to rearD. pelos on
Megachile pacifica, and obtained progeny on 19 of
71 hosts. However, 75% of the eggs laid on M.
pacifica prepupae failed to complete development
to adults. Similarly, we noted significant larval
mortality on M. rotundata hosts and the few
adult progeny obtained were on only 3 of the 10
host replicates.
Comparable data for the progeny ofM. digitata
on the same suite of hosts (except Sphaeropthalma,
unpubl. data) showed that all hosts were accept-


able with adults of both sexes reared from 100% of
the replicates (n = 10 for each host).

Sex Ratios

Grissell (1974) reported male-biased sex ratios
for D. pelos on Sceliphron and Ancistrocerus. In
contrast, we obtained female-biased sex ratios in
nearly every trial on every host (Table 1). These
ratios appeared to vary with the host species. On
the 4 most successful host species, D. pelos pro-
duced an average of 24.7% males; on the two
"marginal" hosts, 43% were male. Overall, the
smallest host species (M. rotundata) yielded the
highest proportion of males (48%). The 13% on
Neobellieria bullata is probably not representa-
tive, as it was based on very few individuals.

Interspecific Competition

In our staged competition experiments with
one female each of D. pelos and M. digitata on a







Florida Entomologist 88(1)


TABLE 1. OFFSPRING PRODUCTION (MEAN SD) AT 25C, 65% RH BY D. PELOS ON VARIOUS HOSTS, ALONE, AND FOR
THE THREE POSSIBLE COMPETITIVE OUTCOMES WITH M. DIGITATA (N = 10).

No. of adult progeny produced
(Mean SD)
No. of hosts Sex ratio
Host species Experiment parasitized Males Females (% males)

Successful hosts
Sceliphron caementarium Alone 10/10 14.5 6.5 31.3 12.1 32
Competition "winner" 1/10 26 25 51
Competition "loser" 7/10 0 0 0
Coexistence 2/10 5.5 6.4 12 8.5 31.4
Trypoxylon politum Alone 10/10 12.9 7.6 44.3 15.8 23
Competition "winner" 0/10 0 0 -
Competition "loser" 9/10 0 0 0
Coexistence 1/10 1 3 25
Sphaeropthalma pensylvanica Alone** 3/3 6.3 1.2 26.7 10.0 19
Anthrax sp. Alone 10/10 13.6 2.7 39.9 4.2 25
Competition "winner" 3/10 16.3 10.2 20.3 7.0 45
Competition "loser" 4/10 0 0 0
Coexistence 3/10 7.3 3.8 13 6.0 36
Marginal hosts*
Megachile rotundata Alone 3/10 3 2.6 3.3 3.5 48
Competition "winner" 1/10 2 1 67
Competition "loser" 3/10 0 0 0
Coexistence 0/10*** 0 0 0
Neobellieria bullata Alone 5/10 0.4 0.5 2.6 0.5 13
Competition "winner" 0 0 0 -
Competition "loser" 9/10 0 0 0
Coexistence 0/10*** 0 0 0

*Marginal hosts are those on which D. pelos managed to produce a few adult progeny in fewer than half of the 10 competition
replicates.
*Limited number of available hosts did not allow use in competition trials.
***In 6 replicates with Meg. rotundata hosts and 1 replicate with N. bullata hosts, no adult progeny of either competitor were
produced.


host, the 2 females seldom coexisted successfully.
Only in 2 replicates with Sceliphron, 1 replicate
with Trypoxylon, and 3 replicates with Anthrax
were hosts successfully shared, as defined by the
subsequent appearance of adult offspring of both
sexes of both species (Table 1, coexistence). Over-
all, D. pelos was the loser in the competition ex-
periments, producing no adult progeny in 20 of
the 30 trials with the three hosts preferred by fe-
males alone (Table 1).
These outcomes were not simply related to
host size. Despite being the smallest of the 3 pre-
ferred hosts, Anthrax was the most likely to be
shared (3 replicates), but D. pelos also was the
outright competition winner in 3 replicates and
the loser in 4 replicates. However, on Sceliphron
sharing occurred in 2 of 10 trials; in 7 trials,
Melittobia were the sole progeny to emerge as
adults, and in 1 trial, only Dibrachys adults
emerged. On Trypoxylon, the largest hosts, 9 of
the replicates resulted in only Melittobia, and in
only 1 trial did adults of both species emerge.


When D. pelos won the competition onAnthrax
hosts the number of males emerging was not dif-
ferent than when alone (no competitor), but the
number of females emerging was fewer than
when alone (Student's t-test, males P = 0.69, fe-
males P = 0.04). When both D. pelos and M. digi-
tata adults emerged after competition for an
Anthrax host, the number ofD. pelos females was
again fewer than when D. pelos was alone (Stu-
dent's t-test, P = 0.005), but not when compared to
when it won outright (Student's t-test, P = 0.24).
Reduced numbers of progeny in competitive situ-
ations is not surprising since the host resource is
not unlimited and, when shared, both host qual-
ity and quantity decline due to host feeding by
each of the female parasitoids.
One straightforward reason why D. pelos suf-
fers most from this competitive interaction was
immediately apparent when larvae ofM. digitata
were observed feeding upon D. pelos larvae (Fig.
Id). Subsequently, emerged M. digitata were ob-
served laying eggs directly upon pupae and even


March 2005







Gonzalez et al.: Development of Dibrachys pelos


TABLE 2. CONVERSION EFFICIENCY* OF DIBRACHYS PELOS AND MELITTOBIA DIGITATA REARED ON DIFFERENT HOSTS;
BASED ON MEANS FOR N = 10.

Conversion Efficiency Index (%)
Weight (g)
Host species (Mean SD) D. pelos M. digitata

Suitable hosts for D. pelos
S. caementarium 0.14 0.003 22.5 25.5
T politum 0.30 0.006 13.7 21.2
Anthrax sp 0.25 0.005 15.3 13.3
Marginal hosts for D. pelos
M. rotundata 0.03 0 13.1 17.3
N. bullata 0.1 0.01 2.3 13.6; 15.9**; 15.3***

*Conversion efficiency = (total number of adult offspring x individual body weight)/ host weight x 100; average weights of indi-
viduals were for D. pelos (males = 0.42 mg, females 0.80 mg) and for M. digitata (males 0.16 mg, females 0.12 mg). Further expla-
nation in text.
**Data from Silva-Torres and Matthews (2003), n = 4, host weight = 0.11 g
***Data from Randall and Guinan (unpubl.), n = 23, host weight = 0.12 g.


on newly emerged adults (Fig. Ib); in the former
case the larvae developed into adult wasps, but
larvae perished in the latter case. Depending on
the host, M. digitata complete development to
adults in 14-24 days (Gonzalez & Matthews
2002), somewhat more rapid than D. pelos devel-
opment in this study.
Differences in fecundity on these hosts may
provide equally or more important explanations
for this disparity. A single M. digitata female on a
Trypoxylon host produces an average of 458 fe-
males and 13 males (unpubl. data), whereas a
single D. pelos female produces the same number
of males but about 10 times fewer females (Table
1). Similar disparities exist for the other hosts, al-
though M. digitata is more broadly polyphagous
(Dahms 1984) and successfully reproduces large
clutches of progeny on both of the hosts that
proved only marginally suitable for D. pelos.
In the 5 experiments (total from all hosts)
where D. pelos "won" in competition against
M. digitata, the proportion of D. pelos males in-
creased substantially from that obtained for a fe-
male ovipositing in the absence of competition
(Table 1). In the 6 replicates (total from all hosts)
where adults of both parasitoids emerged, D. pe-
los' sex ratios remained similar to those obtained
for D. pelos females alone on hosts, although the
proportion of males was elevated for Anthrax
hosts. However, small sample sizes and low num-
bers of progeny in the competition treatments
make it difficult to draw definitive conclusions.
So why doesD. pelos appear to be relatively rare
in field collections of mud dauber nests? In addi-
tion to its poor success in our staged competitions
for hosts, it may be physiologically less efficient in
converting host biomass to parasitoid progeny. To
gain a perspective on this possibility, we compared
the host conversion efficiency of D. pelos and
M. digitata on each of the hosts used in these ex-


periments (Table 2). Melittobia digitata were more
efficient on every host tested but Anthrax. This
suggests that perhaps the hosts we tested were
less suitable for D. pelos development. Perhaps
D. pelos is better adapted to twig-nesting wasps or
some other unknown host, and its occurrence on S.
caementarium was strictly opportunistic and fac-
ultative at sites not concurrently colonized by
Melittobia. (In our extensive field collections of
S. caementarium and T politum nests over several
years in eastern N. America, Melittobia is by far
the commonest parasitoid found [unpubl. data].).
In support of this it is notable that in the extensive
sample of mud dauber nests taken from the same
bridge in Nebraska where D. pelos was originally
collected failed to turn up any Melittobia.

ACKNOWLEDGMENTS

We thank Eric Grissell, USDA Systematic Entomol-
ogy Laboratory, for identification of D. pelos. Alan Kamil
and Robert Anderson, respectively, director and man-
ager of the University of Nebraska Cedar Point Biologi-
cal Station, aided us in numerous ways, including use of
the station facilities during the field work in western
Nebraska. This work was supported in part by a Na-
tional Science Foundation grant to RWM.

REFERENCES CITED

BARBER, C. B., AND R. W. MATTHEWS. 1979. Utilization
of trap nests by the pipe-organ mud dauber, Try-
pargilum politum (Hymenoptera: Sphecidae). Ann.
Entomol. Soc. Am. 72: 260-262.
BROCKMANN, H. J., AND A. GRAFEN. 1989. Mate conflict
and male behaviour in a solitary wasp Trypoxylon
(Trypargilum) politum (Hymenoptera: Sphecidae).
Anim. Behav. 37: 232-255.
CROSS, E. A, M. G. STITH, AND T. R. BAUMAN. 1975. Bio-
nomics of the organ-pipe mud dauber, Trypoxylon
politum (Hymenoptera: Sphecoidea). Ann. Entomol.
Soc. Am. 68: 901-916.











DAHMS, E. C. 1984. A review of the biology of species in
the genus Melittobia (Hymenoptera: Eulophidae)
with interpretations and additions using observa-
tions on Melittobia australica. Mem. Queensland
Mus. 21(2): 337-360.
FLOATE, K., B. KHAN, AND G. GIBSON. 1999. Hymenop-
terous parasitoids of filths fly (Diptera: Muscidae) pu-
pae in cattle feedlots. Can. Entomol. 131(3): 347-362.
GONZALEZ, J. M., AND R. W. MATTHEWS. 2002. Life his-
tory development and sex ratio of Melittobia austral-
ica and M. digitata (Hymenoptera: Eulophidae) on
M. rotundata (Hymenoptera: Megachilidae) and
Trypoxylon politum (Hymenoptera: Sphecidae).
Great Lakes Entomol. 35(1): 85-91.
GRISSELL, E. E. 1974. A new Dibrachys with a key to the
Neartic species (Hymenoptera: Pteromalidae). Flor-
ida Entomol. 57(3): 313-320.
HUNT, J. H. 1993. Survivorship, fecundity, and recruit-
ment in a mud dauber wasp, Sceliphron assimile (Hy-
menoptera: Sphecidae). Ecol. Pop. Biol. 86(1): 51-59.
KROMBEIN, K. V. 1967. Trap-nesting Wasps and Bees:
Life Histories, Nests, and Associates. Smithsonian
Press, Washington, D.C., 570 pp.
MATTHEWS, R. W. 1997a. Unusual sex allocation in a
solitary parasitoid wasp, Sphaeropthalma pensyl-
vanica (Hymenoptera: Mutillidae). Great Lakes En-
tomol. 30: 51-54.
MATTHEWS, R. W. 1997b. Teaching ecological interac-
tions with mud dauber nests. Am. Biol. Teach. 59(3):
152-158.


March 2005


MOLUMBY, A. 1995. Dynamics of parasitism in the or-
gan-pipe wasp, Trypoxylon politum: effects of spatial
scale on parasitoid functional response. Ecol. Ento-
mol. 20: 159-168.
SHAFER, G. D. 1949. The Ways of a Mud Dauber. Stan-
ford University Press, 78 pp.
SILVA-TORRES, C., AND R. W. MATTHEWS. 2003. Devel-
opment of Melittobia australica Girault and M. dig-
itata Dahms (Hymenoptera: Eulophidae) parasitizing
Neobellieria bullata (Diptera: Sarcophagidae) pu-
paria. Neotrop. Entomol. 32: 645-651.
SMITH, L., AND D. A. RUTZ. 1991. Seasonal and relative
abundance of hymenopterous parasitoids attacking
house-fly pupae at dairy farms in central New York.
Environ. Entomol. 20(2): 661-668.
URBAN, A. J., AND C. D. EARDLEY. 1995. A recently in-
troduced sawfly, Nematus oligospilus Forster (Hy-
menoptera: Tenthredinidae), that defoliates
willows in southern Africa. African Entomol. 3(1):
23-27.
VOLKOVA, T., R. W. MATTHEWS, AND M. C. BARBER 1999.
Spider prey of two mud dauber wasps (Hy-
menoptera: Sphecidae) nesting in Georgia's
Okefenokee Swamp. J. Entomol. Sci. 34(3): 322-
327.
WHITEMAN, N. K., AND B. H. P. LANDWER 2000. Parasi-
toids reared from Polistes (Hymenoptera: Vespidae:
Polistinae) nests in Missouri, with a state record of
Elasmus polistis Burks (Hymenoptera: Elasmidae).
J. Kans. Entomol. Soc. 73 (3): 186-188.


Florida Entomologist 88(1)







Tipping et al.: H. zea Dynamics and Parasitism


HELICOVERPA ZEA (LEPIDOPTERA: NOCTUIDAE)
DYNAMICS AND PARASITISM IN MARYLAND SOYBEANS

PHILIP W. TIPPING', CAROL A. HOLKO2 AND RICHARD A. BEAN2
'USDA-ARS, Invasive Plant Research Laboratory, 3205 College Ave., Ft. Lauderdale, FL 33314
e-mail: ptipping@saa.ars.usda.gov

2Maryland Department of Agriculture, Plant Protection Section
50 Harry S. Truman Parkway, Annapolis, MD 21401

ABSTRACT

Larval populations of the corn earworm, Helicoverpa zea (Boddie), were surveyed in soy-
beans from 1995 to 1997 to catalogue larval parasites and quantify rates of parasitism. In
addition, the relationship between moth captures in black-light traps and larval densities in
soybeans was examined. Parasitism was consistently high throughout the region averaging
80.3%, 82.3%, and 73.1% for all dates in 1995, 1996, and 1997, respectively, and appeared to
suppress H. zea populations. The predominate parasite species was Microplitis croceipes
(Cresson) with some parasitism by Cotesia marginiventris (Cresson), Meterous autographae
Meusebeck, and Winthemia rufopicta (Bigot). The date of the peak weekly capture of moths
explained 99.7% of subsequent larval densities in soybeans, while the average weekly moth
catches did not. The earlier moth peak in 1995 corresponded with higher populations of lar-
vae, while the later peaks in 1996 and 1997 were followed by very low, sub-economic larval
populations. Departures from normal for precipitation and temperature during August ex-
plained 99.8% and 95.3%, respectively, of the variation in the date of peak moth capture.

Key Words: Helicoverpa zea, soybeans, parasitism, black-light traps, Lepidoptera

RESUME

Las poblaciones de las larvas del gusano del elote, Helicoverpa zea (Boddie), fueron mues-
treadas en soya desde 1995 hasta 1997 para catalogar los parasites de larvas y cuantificar
la tasa de parasitismo. Ademas, la relaci6n entire las polillas capturadas en trampas de luz
negra y la densidad de las larvas fueron examinadas. El parasitismo fue consistentemente
alto atrav6z de la region con un promedio de 80.3%, 82.3%, y 73.1% para las fechas en 1995,
1996, y 1997, respectivamente, y aparentemente con ello delimito las poblaciones de H. zea.
La especie de parasite predominante fue Microplitis croceipes (Cresson) seguido con el para-
sitismo por parte de Cotesia marginiventris (Cresson), Meterous autographae Meusebeck, y
Winthemia rufopicta (Bigot). La fecha correspondiente al numero mas alto de polillas captu-
radas explica 99.7% de las densidades de larvas subsecuentes sobre la soya, mientras que el
promedio semanal de las polillas capturadas no lo indica. El pico de la poblaci6n mas tem-
prana en 1995 correspondio con poblaciones mas altas de las larvas, mientras que los picos
mas tardes de la poblaci6n en 1996 y 1997 fue seguidos con poblaciones sub-econ6micas de
larvas muy bajas. Las salidas normal de la precipitaci6n y temperature durante agosto ex-
plicaron 99.8% y 95.3%, respectivamente, de la variaci6n en la fecha del pico de la poblaci6n
de polillas capturadas.


The corn earworm, Helicoverpa zea (Boddie), is
a periodic pest of soybeans in Maryland on the
Delmarva peninsula. Herbert et al. (1991) re-
ported that a third of the acreage in Virginia was
treated annually with insecticides to control
H. zea. The dynamics ofH. zea are somewhat dif-
ferent in Maryland because of a lack of a large
overwintering population like parts of Virginia
and North Carolina. Although a small population
does often overwinter in the most southern region
of the peninsula, most of the population migrates
into the area from more southern states (R. A. B.,
unpublished data). Field corn on the Delmarva
peninsula provides a harborage for these immi-


grants which, coupled with continued migration
of adults from further south and lack of parasit-
ism, can result in the maintenance of large popu-
lations of H. zea that pose a threat to soybeans
later in the summer (Zehnder et al. 1990).
The movement of H. zea into soybeans is gov-
erned by an array of factors, the most important
of which is the relative condition of the corn (Stin-
ner et al. 1982). Although corn is preferred over
soybeans by ovipositing H. zea adults, senescing
corn becomes less attractive compared with soy-
beans (Fitt 1989). If the corn stays green for a
longer period, this may allow adjacent soybeans
more time to mature and close their canopies,







Florida Entomologist 88(1)


thereby rendering them less susceptible to H. zea
damage when moths finally shift their oviposition
from mature corn. Corn earworm larvae were al-
most ten times more likely to exceed economic
thresholds when soybean canopies were open as
opposed to closed (Bradley et al. 1986). If soy-
beans are in a susceptible early reproductive
stage like R2 (full bloom) when oviposition occurs,
significant yield losses can result in a relatively
short time (McWilliams 1983; Fehr & Caviness
1977; Kogan 1979).
A survey in Virginia, including the southern
portion of the Delmarva peninsula, found signifi-
cant parasitization ofH. zea in soybeans (Zehnder
et al. 1990). Our objective was to survey soybeans
grown further north for parasite species attacking
H. zea larvae in order to determine the rate of par-
asitism over time, along with other larval mortal-
ity factors like diseases. We sought to examine the
relationship between moth captures in blacklight
traps and larval populations in soybeans.

MATERIALS AND METHODS

Soybean fields were sampled weekly over a
three year period from 1995-1997 during the time
when earworm adults typically shift ovipositing
from corn to soybeans (Aug-Sep for the lower
Eastern Shore of Maryland). Sampling was done
with a standard insect sweep net to take 25
sweeps per sample with 10 samples per field.
Each sample location was at least 50 paces from
the previous one and areas were sampled only
once. Care was taken to sample from the top of the
soybean canopy down through the rest of the
plants. Samplers walked along rows while sweep-
ing alternately in both directions perpendicular to
the row. The sizes of the fields ranged from 0.5 to
53 ha. This method is the recommended scouting
protocol for soybeans in Delaware, Maryland, and
Virginia with economic thresholds of three ear-
worms per 25 sweeps in narrow row soybeans and
five earworms in wide-row soybeans (Anonymous
1995a). The contents of the net were checked and
earworms and other Lepidoptera were removed
with a brush and placed immediately in 30-ml
plastic cups containing standard insect diet
(Southland Products, Inc., Lake Village, AR), one
larva per cup. Larvae were held at 27C and 15 h
photophase until their parasitism status could be
determined. The percentage of parasitism was
calculated and corrected for larval mortality and
the effect caused by the artificial removal of lar-
vae from the potential population of hosts (Mar-
ston 1980). Any larvae that died without parasite
emergence were dissected to check for immature
parasites. Parasite identifications were conducted
by the USDA-ARS Systematic Entomology Labo-
ratory in Beltsville, MD. Voucher specimens of
parasites were placed in the Maryland Depart-
ment of Agriculture insect collection.


The number of adult moths captured in black-
light traps in 5-8 locations each year in the region
was recorded and compared with larval captures.
Blacklight traps were used because the state has
operated a network of traps every year since
1973. These traps were placed in locations that
were unique to each farm but consistent from
year-to-year. Traps were 36.2 cm wide and 129.5
cm tall and used 15 watt blacklight bulbs powered
by 115 V, 60 cycle AC current. Depending on the
location, traps were suspended or placed on tri-
pods that raised them 46-61 cm above the soil sur-
face. Historic data from these traps allowed us to
concentrate our sampling in areas that regularly
experience high levels of H. zea adult captures.
Temperature and precipitation data were col-
lected from a network of weather stations in the
region.
Multiple regression of the departures from
normal in temperature and precipitation during
the months of May through Sep., monthly aver-
ages of adult H. zea captures, and the Julian day
for peak moth capture were used to construct a
model with forward selection (SAS Institute
1990) to identify those variables which predicted
the total number of larvae found in soybeans dur-
ing a season. Monthly averages for adult captures
were calculated by adding the average number of
adults caught per night in a week, including any
overlapping weeks between months, and dividing
by the number of weeks. The peak moth date was
the mid-week Julian day with the highest adult
captures during the season. The averaging period
to determine normals for temperature and precip-
itation was from 1961 to 1990 (Anonymous 1995b,
1996, 1997).

RESULTS AND DISCUSSION

The number ofH. zea larvae found in soybeans
varied significantly among the sample years (Ta-
ble 1). The average number of moths caught per
month in black light traps had no predictive value
for larval numbers in soybeans during the study
period. However, there were consistent peaks in
adult levels every year in late Aug. and early Sep.
(Fig. 1). Our data agree with the findings of Her-
bert et al. (1991) regarding the influence of peak
flights of moths and threats to the soybean acre-
age, namely, that earlier peaks increase risk. The
weekly peak in 1995 was during the period Aug.
14-20, while in 1996 and 1997 both peaks oc-
curred during Sep. 4-10 (Fig. 1). This average
moth flight peak date explained 99.7% of the vari-
ation in larval captures in soybeans (df= 1,1; F =
404.34; P = 0.03).
The reasons for variability of the peaks in
moth flights are unknown but probably are influ-
enced directly by weather, and indirectly by the
weather's effects on the corn crop. Direct effects
might include prevailing winds and storm fronts


March 2005







Tipping et al.: H. zea Dynamics and Parasitism


TABLE 1. INCIDENCE OF NON-PARASITISM MORTALITY FACTORS IN H. zea LARVAE COLLECTED FROM MARYLAND SOY-
BEANS, 1995-1997.

% Dead from disease
No. H. zea1 % H. zea2 % Unknown
Collection dates collected closed N. rileyi Virus mortality

15-Aug-1995 30 70.0 0.0 0.0 16.7
23-Aug-1995 162 50.0 0.0 0.0 12.3
30-Aug-1995 237 40.1 1.3 0.4 17.3
6-Sep-1995 154 32.5 0.0 0.0 13.6
12-Sep-1995 144 33.0 1.4 0.7 14.6
20-Sep-1995 65 7.7 4.6 0.0 12.3
All Dates 1995 762 32.9 1.0 0.3 15.2
13-Aug-1996 7 28.6 0.0 0.0 57.1
20-Aug-1996 9 33.3 0.0 0.0 33.3
4-Sep-1996 58 25.9 5.2 0.0 50.0
19-Sep-1996 61 1.6 34.4 9.8 31.1
All Dates 1996 135 15.6 17.8 4.4 40.7
27-Aug-1997 1 0.0 0.0 0.0 100.0
4-Sep-1997 4 0.0 0.0 0.0 25.0
9-Sep-1997 56 41.1 10.7 0.0 26.7
16-Sep-1997 73 35.6 9.6 0.0 23.3
25-Sep-1997 36 19.4 11.1 5.5 25.0
All Dates 1997 170 50.0 10.0 1.2 25.3

All Dates row in this column refers to the sum total ofH. zea larvae found that year.
'All Dates row in all remaining columns refers to the variable mean for that year.


which bring in migrants from the south or the
temperature, which controls the rate of develop-
ment of larvae in the corn. In our study, the aver-
age departures from normal precipitation and
temperature in Aug. explained 99.8% and 95.3%,
respectively, of the variation in the date of peak
moth flights. Practical experience and other re-
search has previously established a link between


S 30-
30
so

20

a.
S10


Sample Week

Fig. 1. Mean weekly capture of corn earworm moths
from 1995-1997 in five to eight blacklight traps located
in a three county area in the lower Eastern Shore region
of Maryland.


the weather, especially precipitation during the
summer, and the condition of the corn which de-
termines how long the crop is attractive to gravid
females of H. zea. Hot, dry conditions likely in-
crease the rate of larval development in corn,
leading to an earlier moth peak while, at the same
time, shortening the period when the corn re-
mains attractive as an oviposition site. Usually,
the aforementioned weather conditions will also
retard the development of the soybean crop, slow-
ing canopy closure and delaying maturities to
stages more susceptible to damage from larval
feeding. These conditions normally trigger alert
warnings to growers from local organizations like
the Cooperative Extension Service and state de-
partments of agriculture.
In contrast, wetter, cooler conditions may act
to maintain preferred oviposition sites for H. zea
in the corn, by slowing development of the crop,
thereby allowing the soybean crop to progress
past the earlier, more vulnerable reproductive
stages. Pressure in soybeans from H. zea larvae
was highest in 1995 when the lower Eastern
Shore areas experienced a severe drought (Fig. 2).
In contrast, 1996 and 1997 experienced average
to above average precipitation and H. zea popula-
tions were lower in soybeans (Fig. 2).
Over the period from 1995-1997, Microplites
croceipes (Cresson) was the most frequently en-
countered parasite species attacking H. zea in
soybeans (Fig. 3). Zehnder et al. (1990) and Her-


- 1995
........ 1996
--- 1997






/...











4-




E -
E 2-
0
-





I-
Cr


E -2-

-3



15
-


April May June July Aug Sept


April May June July Aug Sept

Fig. 2. Departures from mean temperature and pre-
cipitation during 1995-1997 from seven stations in the
lower Eastern Shore region of Maryland.


bert et al. (1993) found similar results with this
parasite. This native species is an important par-
asite of H. zea and other Heliothines (Stadel-
bacher et al. 1984; Bottrell et al. 1968; King et al.
1985). Other parasite species collected included
Cotesia marginiventris (Cresson) (Hymenoptera:
Braconidae), Meteorus autographae Muesbeck
(Hymenoptera: Braconidae), and Winthemia rufo-
picta (Bigot) (Diptera: Tachinidae). In 1996, one
H. zea larva was parasitized by Glyptapanteles
militaris (Walsh) (Hymenoptera: Braconidae).
The weekly increase in parasitism was consis-
tent across years with an average increase of
13.9%, 14.7%, and 22.2% each week during 1995,
1996, and 1997, respectively (Fig. 3). Only in 1995


March 2005


T -^--i-T-r..^
o--*o8-e-So o-B



1996 U
/





0 /p
/
/

- 0------. .,-^....
o--o' -Q 01


Microplitis croceipes
-........0... Cotesia marginiventris
----v--- Meteorus autographae
--v---- Winthemia rufopicta
-e Total Effective Parasitism

Fig. 3. Mean estimated effective parasitism ofH. zea
larvae collected from Maryland soybean fields from
1995-1997. Estimated effective parasitism (EEP) is cal-
culated by first determining apparent parasitism (AP):
AP = no. parasitized H. zea/no. parasitized H. zea + no.
healthy H. zea (Marston 1980). EEP = AP + AP(1-AP)
(Marston 1980).


Florida Entomologist 88(1)


1995


*-_41


-3--







Tipping et al.: H. zea Dynamics and Parasitism


were economic thresholds exceeded at some sites
and growers prepared to apply insecticides. How-
ever, most of the cooperating farmers held off
treating soybeans that year because the drought
had degraded the value of their stands. These dry
conditions resulted in few cases of disease among
the collected larvae (Table 1). In contrast, the inci-
dence of larvae with symptoms typical of infection
byNomuraea rileye (Farlow) and a virus increased
in the next two years, which experienced wetter
and cooler conditions than normal (Table 1).
Overall, this study demonstrated the utility of
considering the departures from normal for pre-
cipitation, and perhaps temperature in Aug., in
predicting risk to the soybean crop on the Del-
marva peninsula from attack by H. zea. We do not
suggest that this method take the place of cumu-
lative experience or information from other
sources, including sampling corn, nor does it pro-
vide an alternative for scouting soybeans and
making control decisions. Rather, it supports ex-
isting conventional wisdom for managing this
pest. However, further examination of the rela-
tionship between peak moth flights and weather
conditions may provide growers with a quick and
inexpensive method for predicting risk to their
soybean crop and targeting their scouting efforts.
Departure from normal data are readily available
and can be quickly utilized to support decisions
on the deployment of scouts.
This study also identified parasite species and
quantified parasitism over the crucial period
when soybeans are most vulnerable to H. zea at-
tack. Although the ability of parasites to suppress
H. zea populations in soybeans was not assessed,
it is clear that a significant portion of the pest
populations are consistently and heavily attacked
by a suite of parasites, most notably M. croceipes.
This species has been shown to be unaffected by
differences in soybean cultivars such as leaf pu-
bescence (Tillman & Lambert 1995). It also will
search non-crop plants for hosts, such as Gera-
nium dissectum L., a species with several close
relatives that are common on the Delmarva pen-
insula (Kaas et al. 1993; Tatnall 1946). Hopper
and King (1986) found that this parasite exhib-
ited a linear functional response to host densities,
a characteristic which should make it an impor-
tant factor in suppressing H. zea populations, es-
pecially given the wide range of larval densities
present in soybeans during this study. Judging by
the rapid and regular disappearance ofH. zea lar-
vae from fields, parasites like M. croceipes may
play a significant role in the population dynamics
of this pest in Maryland soybeans.


ACKNOWLEDGMENT

We thank P. M. Marsh (Braconidae) and N. E. Wood-
ley (Tachinidae), USDA-ARS Systematic Entomology
Laboratory for identifying parasite species. We also


thank the following growers for allowing us to sample
their fields: Philip Jackson, Edward Wright, Francis
Wright, John Brinsfield, Balvin Brinsfield Jr., Bill
Johnson, Wes Messick, Bill Outten, Gene Spears,
Calvin Taylor, Jr, Richard Robinson, Tommy Wheatley,
Dale Reagan, Sonny Maucus, and Catherine Brinsfield.
Dodie Ferrier, Emily Rhea, and Richard Feeney as-
sisted in sample collection and processing. This re-
search was funded in part by the Maryland Soybean
Board.

REFERENCES CITED

ANONYMOUS. 1995a. Pest Control Recommendations for
Field Crops. Bulletin 237. Cooperative Exten. Ser-
vices: Univ. of MD, Univ. of DE, VPI.
ANONYMOUS. 1995b. Climatological Data, Maryland
and Delaware. NOAA National Climatic Data Cen-
ter, Asheville, NC.
ANONYMOUS. 1996. Climatological Data, Maryland and
Delaware. NOAA National Climatic Data Center,
Asheville, NC.
ANONYMOUS. 1997. Climatological Data, Maryland and
Delaware. NOAA National Climatic Data Center,
Asheville, NC.
BOTTRELL, D. G., J. H. YOUNG, R. G. PRICE, AND R. H.
ADAMS. 1968. Parasites reared from Heliothis spp. in
Oklahoma in 1965 and 1966. Ann. Entomol. Soc. Am.
61: 1053-1055.
BRADLEY, J. R. JR., G. A. HERZOG, S. H. ROACH, R. E.
STINNER, AND I. TERRY. 1986. Cultural control in
southeastern United States cropping systems, pp.
22-28 In Theory and Tactics of Heliothis Population
Management. I. Cultural and Biological Control.
South. Coop. Series. Bull. 316.
FEHR, W. R., AND C. E. CAVINESS. 1977. Stages of Soy-
bean Development. Iowa State Univ. Special Rep. 80.
11 pp.
FITT, G. P. 1989. The ecology of Heliothis species in re-
lation to agroecosystems. Ann. Rev. Entomol. 34: 17-
52.
HERBERT, D. A., JR., G. W. ZEHNDER, AND E. R. DRAY.
1991. Evaluation of a pest advisory for corn earworm
(Lepidoptera: Noctuidae) infestations in soybean. J.
Econ. Entomol. 84: 515-519.
HERBERT, D. A., JR., G. W. ZEHNDER, J. SPEESE, AND J.
E. POWELL. 1993. Parasitization and timing of dia-
pause in Virginia Microplitis croceipes (Hymenop-
tera: Braconidae): implications for biocontrol of Heli-
coverpa zea (Lepidoptera: Noctuidae) in soybean.
Environ. Entomol. 22: 693-698.
KASS, J. P., S. B. RAMASWAMY, AND G. W. ELZEN. 1993.
Behavioral time budget and periodicity exhibited by
Microplitis croceipes in field cages with Heliothis
virescens on spring host plants. Entomophaga 38:
143-154.
HOPPER, K. R., AND E. G. KING. 1986. Linear functional
response of Microplitis croceipes (Hymenoptera:
Braconidae) to variation in Heliothis spp. (Lepidop-
tera: Noctuidae) density in the field. Environ. Ento-
mol. 15: 476-480.
KING, E. G., J. E. POWELL, AND R. J. COLEMEN. 1985. A
high incidence of parasitism of Heliothis spp. (Lep.:
Noctuidae) larvae in cotton in southeastern Arkan-
sas. Entomophaga 30: 419-426.
KOGAN, M. 1979. Insect problems of soybeans in the
United States, pp. 303-325 In T T. Corbin [ed.] World







60 Florida Entc



Soybean Research Conference II: Proceedings. West-
view, Boulder, CO.
MARSTON, N. L. 1980. Sampling parasitoids of soybean
insect pests, pp. 481-504 In M. Kogan and D. C. Her-
zog [eds.], Sampling Methods in Soybean Entomol-
ogy. Springer, New York.
MCWILLIANS, J. M. 1983. Relationship of soybean pod
development to bollworm and tobacco budworm
damage. J. Econ. Entomol. 76: 502-506.
SAS INSTITUTE. 1990. SAS Users's Guide: Statistics.
SAS Institute, Cary, NC.
STADELBACHER, E. A., J. E. POWELL, AND E. G. KING.
1984. Parasitism of Heliothis zea and H. virescens
(Lepidoptera: Noctuidae) larvae in wild and culti-
vated host plants in the delta of Mississippi. Envi-
ron. Entomol. 13: 1167-1172.


)m


ologist 88(1) March 2005



STINNER, R. E., J. REGNIERE, AND K. WILSON. 1982. Dif-
ferential effects of agroecosystem structure on dy-
namics of three soybean herbivores. Environ.
Entomol. 11: 538-543.
TATNALL, R. R. 1946. Flora of Delaware and the Eastern
Shore. Society of Natural History of Delaware,
Wilmington, DE.
TILLMAN, P. G., AND L. LAMBERT. 1995. Influence of soy-
bean pubescence on incidence of the corn earworm
and the parasitoid, Microplitis croceipes. Southwest.
Entomol. 20: 181-185.
ZEHNDER, G. W., D. A. HERBERT, R. M. MCPHERSON, J.
SPEESE III, AND T. MOSS. 1990. Incidence of Helio-
this zea (Lepidoptera: Noctuidae) and associated
parasitoids in Virginia soybeans. Environ. Entomol.
19: 1135-1140.







Evans & Pefia: Fidiobia dominica, New Species


A NEW FIDIOBIA SPECIES (HYMENOPTERA: PLATYGASTRIDAE)
REARED FROM EGGS OF DIAPREPES DOUBLIERII
(COLEOPTERA: CURCULIONIDAE) FROM DOMINICA

GREGORY A. EVANS' AND JORGE E. PENA2
1ARS, USDA/APHIS-PPQ/BARC-West, Bldg. 005, Room 137, Beltsville, MD 20705

2Tropical Research and Educational Center, University of Florida, Homestead, FL 33031

ABSTRACT

A new species of the genus Fidiobia reared from the eggs of Diaprepes doublierii collected in
Dominica is described and illustrated. A key to the New World species of the genus Fidiobia,
a host and distribution table of the 13 known Fidiobia species, and a summary of the efforts
made to introduce natural enemies of Diaprepes species into Florida are provided.

Key Words: Platygastridae, Fidiobia, Curculionidae, Diaprepes, citrus weevil, biological con-
trol

RESUME

Se describe y se ilustra una nueva especie del g6nero Fidiobia criada de los huevos de Dia-
prepes doublierii recolectados en Dominica. Se provee una clave de las species de Fidiobia
presents en el Nuevo Mundo, y un cuadro del los hospederos y distribuci6n de las 13 espe-
cies de Fidiobia conocidas. Se comentan los esfuerzos hechos para introducir enemigos nat-
urales de species de Diaprepes en el estado de Florida.


Translation provided by the authors.


In April of 2003, J. Pefia, R. Duncan, C. McCoy,
and J. Alegria, while conducting a survey of the
egg parasitoids of Diaprepes species on citrus in
Dominica, reared a new species of Fidiobia
[Platygastridae] from eggs of Diaprepes doub-
lierii, and transported it to the quarantine facility
in Homestead, Florida for testing and subsequent
introduction into Florida. After commenting on
the species to Dr. Lubomir Masner, he suspected
that it was the same undescribed species that he
had collected in Dominica in 1994 and that J. Eti-
enne had reared from Diaprepes abbreviatus in
Guadeloupe in 1994. Dr. Masner sent specimens
from these collections to the senior author, who
determined that they were the same species that
is described herein.
Ashmead (1894) erected the genus Fidiobia
based upon specimens collected in Ohio (USA) and


designated Fidiobia flavipes Ashmead as the type
species. Including the new species described
herein, the genus contains 13 species (Table 1); of
these, 3 were described from the Nearctic, 4 from
the Neotropical, 4 from the Palearctic and 2 from
the Afrotropical region. Although no species of this
genus have yet been described from the Oriental
region, Masner and Huggert (1989) stated that the
genus is worldwide in distribution with many un-
described species. With the exception of Fidiobia
flavipes, which was reared from chrysomelid eggs,
all of the other Fidiobia species for which the host
records are known were reared from curculionid
eggs. Readers are referred to Masner & Huggert
(1989) for a key to the genera of Platygastridae
which includes a diagnosis, discussion and illustra-
tions for each platygastrid genus, and to Schauff
(1987) for the key to the parasites of citrus weevils.


KEY TO NEW WORLD SPECIES OF FIDIOBIA (FEMALES)

1. Notauli absent; head and thorax black, gaster lighter; legs brown except for yellow tarsi
and apices of tibia .............................................................. citri (N ixon)
lb. Notauli present, either 2 thin, hairline streaks or 2 very broad, wedge-shaped cavities;
body and leg color variable .............................................................. 2
2(1) Notauli consisting of 2 thin, hairline streaks ................................................. 3
2b. Notauli consisting of 2 very broad, wedge-shaped cavities ....................................... 4
3(2b) Gaster bright yellow; head and mesoscutum brown; legs yellow; F2 quadrate ......... dominica, n. sp.







Florida Entomologist 88(1)


TABLE 1. HOST AND DISTRIBUTION OF FIDIOBIA SPECIES.

Species Host Distribution Citation

Fidiobia asina (Loiacano) Curculionidae: Argentina Loiacano (1982)
Naupactus xanthographus
Fidiobia benjamin (Nixon) Curculionidae: Kenya Nixon (1969)
Entypotrachelum micans
Fidiobia bonariensis unknown Argentina Brethes (1916)
(Brethes)
Fidiobia citri (Nixon) Curculionidae: Diaprepes spp. Jamaica Nixon (1969)
Fidiobia danielssoni Buhl unknown South Africa Buhl (2001)
Fidiobia dominica Evans Curculionidae: Dominica, Guadeloupe Evans & Peia
& Peia Diaprepes doublerii, D. abbre- (current paper)
hiatus
Fidiobia drakei (Oglobin) unknown USA: Iowa Oglobin (1944)
Fidiobia flavipes Ashmead Chrysomelidae: Fidia viticida USA: Ohio, New York Ashmead (1894)
Fouts (1924)
Ellis (1973)
Fidiobia hofferi Kozlov unknown Czech Republic, Norway, Kozlov (1978)
Sweden
Fidiobia polita Buhl unknown Sweden Buhl (1999)
Fidiobia pronotata Szabo unknown Hungary, Moldavia Szabo (1958)
Fidiobia rugosifrons Curculionidae: Hypera postica Canada, USA: Indiana, Crawford (1916)
Crawford Pennsylvania; Panama; Cen- Buhl (1998, 1999,
tral Asia, Sweden, Norway 2002)
Fidiobia syngorgum unknown Norway Buhl (1999)
(Keiffer)


3b. Body dark brown to black with metasoma gradually becoming lighter towards apex;
coxae, femora and central portion of tibia II and III brown; F2 transverse ............ asina (Loiacano)
4(2b) Antennae completely yellow; body brown ...................................... flavipes Ashmead
4b. Antennae yellow with dark brown club; body black ............................................ 5
5(4b). Fl short, rectangular, about as long as F2; head and mesoscutum apparently without
fine thimble-like sculpture ................................................... drakei (Oglobin)
5b. Fl long, trapezoidal, about 1.5x as long as F2; head and mesoscutum with fine,
thimble-like sculptures ................................................. rugosifrons (Crawford)
*Fidiobia bonariensis (Brethes) was not included in key because the description of the species lacked sufficient de-
tail to distinguish it from other species; however based on the coloration and the shape the antennal segments, we
suspect that it is very similar to, if not conspecific with, F rugosifrons (Crawford).


Fidiobia dominica Evans and Pefa, n. sp.

Female (Figs. 1, 2, 4). Length: 1.4-1.45 mm.

Diagnosis

Fidiobia dominica can be distinguished from
all of the other Fidiobia species by having the
gaster entirely yellow and the notauli repre-
sented by thin, hairline streaks. It is most similar
to F asina in that both species have the notauli
represented by a thin, hairline streak, but can be
distinguished from the latter species by having
the gaster and legs bright yellow and the F2 an-
tennal segment quadrate; whereas in F asina,
the body is dark brown to black with the gaster


becoming lighter towards the apex; the coxae,
femora and central portion of tibia II and III are
brown, and F2 is transverse.

Description

Color (Fig. 1). Head and thorax dark brown to
black; gaster, legs and antennal scape, pedicel
and funicle yellow; antennal club dark brown;
wings slightly infuscate.
Head (Fig. 1). About as wide as thorax, subel-
lipsoidal with rounded vertex; eyes glabrous with
scattered minute setae; malar sulcus absent;
cheeks smooth; mandibles short, bidentate; pal-
pal formula 1-1; tongue (galea) with 1 central peg
and 2 pairs of marginal pegs.


March 2005







Evans & Pefia: Fidiobia dominica, New Species


Antennae (Fig. 2). With 4 funicle segments,
club 3-segmented and compact. Length, width
and length/width measurements for antenna
segments as given in Table 2.
Thorax (Fig. 1). Midlobe distinctly wider than
long with elongate reticulations along the ante-
rior margin and sublaterally with smooth central
area and lateral margins, and 34-36 short, thin
setae; notauli thin, hairstreak-like extending
from the posterior margin to about 3/4 to the an-
terior margin; scutellum smooth with placoid sen-
sillae widely separated (42.5) and with 10 slender
setae along the posterior margin; metanotum
smooth, slightly shorter than half the length of
the scutellum; propodeum long with numerous
long hairs.
Forewing (Fig. 4). Elongate and slender 2.73 as
long as wide, submarginal vein short (87.5) about
0.24x as long as the forewing, stigmal vein with 3
sensoriae and a single long seta, marginal fringe
0.15x as long as maximum width of forewing.
Legs (Fig. 1). Middle leg tibia (200) and basi-
tarsus (67.6), tibial spur (25).
Gaster (Fig. 1). Tergite I wider than long, 0.88
times as long as gastral tergites II-VI, smooth ex-
cept for elongate reticulations along the submar-
ginal area extending from the anterior margin to
about 3/4 to the posterior base, with long hairs
along the anterior margin and in a pair of ellipti-
cal-shaped areas along the submarginal area,
tergites II-IV reticulate centrally and smooth lat-
erally, tergites V-VI smooth; ovipositor arising at
base of gaster and extending to the posterior
apex, not exserted.
Male (Figs. 3, 5). Similar to female in color and
structure with segments of antennal club more
separated (Fig. 3) with measurements as given in
Table 2 and genitalia as shown in Figure 5.


Specimens Examined and Deposition

Holotype female: Dominica: Parish, Cuba,
26.vi.2003, R. Duncan and J. Alegria, ex. egg
mass ofDiaprepes doublierii on Citrus sp., depos-
ited in the U.S. National Museum of Natural His-
tory (USNM); Paratypes-Dominica: Grand Bay,
28.iv.2003, J. Pefia and C. McCoy, ex. egg mass of
Diaprepes doublierii on Citrus sp.; Dominica:
Syndicate, 28.iv.2003, J. Pefia and C. McCoy, ex.
egg mass ofDiaprepes doublierii on Citrus sp.; 2
females, Dominica, St. Peters Parish, Morne, Dia-
bloton, 700-900 m 26.xi.1004, L. Masner, virgin
forest; 7 females and 9 males, Guadeloupe, Bouil-
lante Pigeon, 24.vi.1994, J. Etienne, ex. Dia-
prepes abbreviatus egg mass on Citrus sp.,
deposited in the Florida Collection of Arthropods,
Gainesville, Florida and in the Canadian Na-
tional Collection, Ottawa, Canada.

ETYMOLOGY

This species is named for the country where it
was discovered.

DISCUSSION

Diaprepes abbreviatus (Linnaeus) was intro-
duced into Florida in 1964 (Woodruff 1964) and
since has become a serious pest of citrus through-
out much of the central and southern Florida. A
biological control program was initiated to de-
velop and implement strategies to manage the
root weevil, D. abbreviatus in response to the
spread of the weevil in Florida and latest infesta-
tions in Texas and California (Knapp 1985; Wood-
ruff 1968; McCoy & Simpson 1994; Mannion et al.
2003; Godfrey et al. 2002). Because of a lack of


TABLE 2. MEASUREMENTS (lIM) OF HOLOTYPE FEMALE AND ALLOTYPE MALE FIDIOBIA DOMINICA.

Female holotypee) Male (Allotype)

segment length width length/width segment length width length/width

Scape 152.5 42.5 3.59 Scape 125.0 47.5 2.63
Pedicel 62.5 22.5 2.78 Pedicel 52.5 27.5 1.91
F1 30.0 20.0 1.50 F1 43.7 25.0 1.75
F2 17.5 22.5 0.78 F2 17.5 20.0 0.88
F3 15.0 22.5 0.67 F3 17.5 22.5 0.78
F4 17.5 30.0 0.58 F4 17.5 25.0 0.70
C1 60.0 57.5 1.04 C1 30.0 37.5 0.80
C2 37.5 57.5 0.65 C2 25.0 37.5 0.67
C3 50.0 47.5 1.05 C3 42.5 35.0 1.24
Forewing 362.5 132.5 2.73
Scutellum 62.5 170.0 0.36
Metanotum 30.0 200.0 0.15
Propodeum 80.0 237.5 0.37
GasterT1 265.0 315.0 0.84
Gaster T2-T6 300.0 315.0 0.95








Florida Entomologist 88(1)


-r,



a''

'/>'
;1.

--.- -J
K


Figs. 1-5. Fidiobia dominica. 1) female habitus, 2) female antenna, 3) male antenna, 4) female forewing, 5) male
genitalia.



native egg parasitoids found attacking this weevil initiated to introduce, release, and evaluate can-
in citrus orchards in Florida (Hall et al. 2001) and didate egg parasitoids from the Caribbean Region
past failures of classical biological control of this into Florida (Pefia et al. 1998; Pefia & Amalin
weevil (Beavers et al. 1980), renewed efforts were 2000; Hall et al. 2002). For instance, Brachyufens


March 2005







Evans & Pefia: Fidiobia dominica, New Species


osborni (Dozier), a trichogrammatid wasp de-
scribed from specimens reared from Diaprepes
abbreviatus in Puerto Rico was introduced into
Florida but has not been recovered fromD. abbre-
viatus in Florida, although it has been reared
from eggs ofPachnaeus opalus on citrus.
Foreign exploration for egg parasites of Dia-
prepres and other genera of citrus weevils has
been conducted in several Caribbean and Central
American countries (Peia et al. 2000; Hall et al.
2002) to introduce them into Florida for classical
biological control ofDiaprepes abbreviatus. Quad-
rastichus haitiensis (Gahan) (Hymenoptera: Eu-
lophidae), previously reported under the name
Tetrastichus haitiensis (Schauff 1987), was re-
leased during the 1970s in Apopka (central Flor-
ida) and in West Palm Beach (southeastern
Florida) (Beavers & Selhime 1975), but failed to
establish (Beavers & Selhime 1975). In 1998,
Hall, Nguyen and Stansly obtained the parasitoid
from Puerto Rico and attempted to introduce it
into Florida again. In 2002, subsequent releases
of the parasitoid were made in citrus and orna-
mental fields in Florida. Quadrastichus haitiensis
(Gahan) is established in the southern part of the
state (Miami-Dade County), but has failed to es-
tablish in mid, central, and southwest Florida
(Peia et al., unpublished data).
Ceratogramma etiennei Delvare (Hymenop-
tera: Trichogrammatidae), is a highly specific egg
parasitoid of D. abbreviatus from Guadeloupe
(Etienne et al. 1990). This species was introduced
into Florida from Guadeloupe in 1997 (Pefa et al.
1998) and released during 1998 in citrus, orna-
mental fields and natural habitats infested with
the Diaprepes root weevil but failed to establish
(Peia et al. unpublished data).
A third parasitoid, Aprostocetus gala (Walker)
(Hymenoptera: Eulophidae), also known as Tet-
rastichus gala Walker and Aprostocetus vaquita-
rum Wolcott, was found in high numbers
parasitizing Diaprepes root weevil eggs in the Do-
minican Republic during 2000 (Peia & McCoy,
pers. obs.) and was subsequently released during
2001 at several sites across Florida. Again, while
the parasitoid is successfully established in orna-
mental and citrus groves in Miami-Dade County,
its recovery continues to be erratic in other parts
of the state (Peia et al. unpublished data).
Fidiobia dominica was found parasitizing 11%
of collected eggs (n = 35 eggs) in the survey for egg
parasitoids of Diaprepes spp. conducted in Do-
minica. In quarantine, when egg masses of Dia-
prepes abbreviatus are exposed to the parasitoid,
percent parasitism ranged from 26-65%, depend-
ing on the substrate on which the host eggs are
laid, e.g., host plant versus wax paper or con-
cealed eggs versus non-concealed eggs (Duncan &
Peia, unpubl.). Under quarantine conditions,
25C, 75-80% Rh., 12:12 L:D h photoperiod, Fidi-
obia dominica deposits eggs singly in eggs of the


Diaprepes weevil. The eggs hatch in approxi-
mately 1 d and the free-living first instar feeds di-
rectly upon the fluid of the weevil egg. Parasitized
eggs are a dark gold color. Parasitoids will emerge
from parasitized eggs within approximately 10-
12 days. If fed honey and water, Fidiobia domin-
ica adults live a range of 4 to 8 days. A parasitized
egg mass can produce 7 to 19 parasitoids depend-
ing on the substrate where the weevil eggs are
laid. For instance, a higher parasitoid emergence
is observed when eggs are laid on leaves com-
pared to artificial substrates, such as wax paper
(Duncan & Pefia, unpubl.). Fidiobia dominica has
been successfully reared for several generations
on Diaprepes abbreviatus eggs in quarantine;
when approved, it will be released at various sites
in Florida.

ACKNOWLEDGMENT

We thank C. McCoy, R. Duncan, and J. Alegria, who
along with the junior author, discovered this species in
Dominica, and L. Masner for comments on the genus
Fidiobia and this new species and for the loan of speci-
mens from Dominica and Guadeloupe. We thank J. Eti-
enne, who collected the specimens in Guadeloupe, and
P. Hill for providing assistance during exploratory trips.
This study was funded in part by grants from CSREES,
T-STAR and FCPRAC. This is Florida Agricultural Ex-
periment Station Journal Series R-10557.

REFERENCES CITED

ASHMEAD, W. H. 1894. A new genus and species of Proc-
totrypidae and a new species of Brachysticha, bred
by Prof. F. M. Webster. J. Cincinnati Soc. of Natural
History. 17: 170-172.
BEAVERS, J. B., S. A. LOVESTRAND, AND A. G. SELHIME.
1980. Establishment of the exotic parasite Tetrasti-
chus haitiensis (Hym: Eulophidae) and recovery of a
new Trichogramma (Hym: Trichogrammatidae) from
root weevil egg masses in Florida. Entomophaga 25:
91-94.
BEAVERS, J. B., AND A. G. SELHIME. 1975. Further at-
tempts to establish the weevil egg parasite, Tetrasti-
chus haitiensis in Florida. Florida Entomol. 58: 29-31.
BRETHES, J. 1916. Hym6nopteres parasites de
l'Am6rique meridionale. Anales del Museo Nacional
de Historia Natural de Buenos Aires 27:401-430.
BUHL, P. N. 1998. On some new or little known NW Eu-
ropean species of Platygastridae (Hymenoptera,
Proctotrupoidea). Fragmenta Entomologica, Roma
30: 295-334.
BUHL, P. N. 1999. A synopsis of the Platygastridae of
Fennoscandia and Denmark (Hymenoptera, Platy-
gastroidea). Entomofauna, Zeitschrift fur Entomolo-
gie 20(3): 17-52.
BUHL, P. N. 2001. Taxononic notes on Platygastridae
(Hymenoptera, Platygastroidea) Entomofauna,
Zeitschrift fur Entomologie 22(3): 17-40.
BUHL, P. N. 2002. Contributions to the platygastrid
fauna of Panama. Entomofauna, Zeitschrift fur En-
tomologie 23: 309-332.
CRAWFORD, J. C. 1916. Some new American Hymenop-
tera. Insecutor Inscitiae Menstruus. 4: 135-144.











DELVARE, G. 1988. Ceratogramma etiennei n. sp., Para-
site a la Guadeloupe de Diaprepes abbreviatus L.
(Hymenoptera: Trichogrammatidae; Coleoptera:
Curculionidae). Revue francais Entomologie 10: 1-4.
ELLIS, C. R. 1973. Parasitism of Hypera postica eggs at
Guelph, Onario, by Patasson luna and Fidiobia rug-
osifrons. J. Econ. Entomol. 66: 1059-1061.
ETIENNE, J., H. MAULEON, AND B. PINTURAU. 1990. Bio-
logie et dynamiquex de Ceratogramma etiennei (Hy-
menoptera: Trichogrammatidae) parasite de
Diaprepes abbreviatus (L.) (Coleoptera: Curculion-
idae) en Guadeloupe. Les Colloques. INRA 58:459-68.
FOUTS, R. M. 1924. Revision of the North American
wasps of the subfamily Platygasterinae. Proceedings
of the United States National Museum 63(15): 1-145.
GODFREY, K., B. GRAFTON-CARDWELL, J. PENA, C. MC-
COY, AND R. LUCK. 2002. Diaprepes root weevil. UC
Statewide IPM Program and Center for Invasive
Species Research booklet, 4 p.
HALL, D. G., J. E. EGER, J. PENA, R. DUNCAN, C.
O'BRIEN, G. A. EVANS, AND C. MCCOY. 2002. Explora-
tion in Belize for parasitoids attacking eggs of citrus
weevils, and an evaluation ofPediobius irregularis and
Horismenus bennetti (Hymenoptera: Eulophidae) as
potential biological control agents of Diaprepes abbre-
viatus and Pachnaeus litus (Coleoptera: Curculion-
idae). Florida Entomologist 85(4): 660-663.
HALL, D., J. PENA, R. FRANQUI, R. NGUYEN, P. STANSLY,
C. MCCOY, S. LAPOINTE, R. ADAIR, AND B. BULLOCK.
2001. Status of biological control by egg parasitoids of
Diaprepes abbreviatus (Coleoptera: Curculionidae) in
citrus in Florida and Puerto Rico. BioControl 46:61-70.
KNAPP, J. L. 1985. The citrus root weevils in Florida: an
extension service perspective. Florida Entomol. 68:
368-370.
KOZLOV, M. A. 1978. Superfamily Proctotrupoidea, pp.
538-664 In G. S. Medvedev [ed.], Determination of
Insects of the European Portion of the USSR. Vol. 3,
part 2. Nauka, Leningrad. 758 pp.
LOIACONO, M. S. 1982. Un nuevo platygatrido (Hy-
menoptera-Platygastridae) criado de huevos de
Naupactus xanthographus Germ. (Coleoptera-Cur-
culionidae). Revista de la Sociedad de Entomologia
de Argentina 41(1-4) 85-88.
MANNION, C., A. HUNSBERGER, J. E. PENA, AND L. Os-
BORNE. 2003. Oviposition and larval survival of Dia-
prepes abbreviatus on different host plants. Florida
Entomol. 86: 165-173.
MASNER, L., AND L. HUGGERT. 1989. World review and
keys to genera of the subfamily Inostemmatinae
with reassignment of the taxa to the Platygastrinae
and Sceliotrachelinae (Hymenoptera: Platyga-
stridae). Mem. Entomol. Soc. Canada 147: 1-214.


March 2005


McCoY, C., AND S. E. SIMPSON. 1994. Past and current
IPM strategies to combat the spread of Diaprepes ab-
breviatus in Florida citrus. Proc. Caribbean Food
Crops Soc., St. Thomas 30: 247-255.
NIXON, G. E. J. 1969. Two new species of Platystasius
Nixon with a note on the generic relationship be-
tween Platystasius and Fidiobia (Hymenoptera:
Platygasteridae). Proc. Entomol. Soc. Washington.
71: 445-449.
OGLOBIN, A. A. 1944. Two new species of Proc-
totrupoidea from Iowa (Hymenoptera). Proc. Ento-
mol. Soc. Washington 46: 155-158.
PENA, J. E., AND D. M. AMALIN. 2000. Biological control
of Diaprepes abbreviatus by parasitoids, pp. 66-76 In
S. H. Futch [ed.] Diaprepes Short Course. Coopera-
tive Extension Service Florida Agricultural Experi-
ment Station. Citrus Research & Education Center,
Lake Alfred, FL. March 22, 2000.
PENA, J. E., J. ETIENNE, R. DUNCAN, AND J. PINTO. 1998.
Introduction of Ceratogramma etiennei (Hy-
menoptera: Trichogrammatidae) for biological control
of Diaprepes abbreviatus in Florida, USA, pp. 145-148
In S. Hassan [ed.], Egg Parasitoids, 5th International
Symposium, IIBC, Cali, Colombia, Berlin.
PENA, J. E., D. G. HALL, R. NGUYEN, R. DUNCAN, D.
AMALIN, P. STANSLY, C. MCCOY, R. ADAIR, S.
LAPOINTE, H. BROWNING, AND J. KNAPP. 2000. Ef-
forts toward establishment of biological control
agents of Diaprepes root weevil: Fact Sheet ENY-
643, Institute of Food and Agricultural Sciences,
University of Florida, Gainesville, FL. 5 pp.
SCHAUFF, M. E. 1987. Taxonomy and identification of
the egg parasites (Hymenoptera: Platygastridae,
Trichogrammatidae, Mymaridae, and Eulophidae)
of citrus weevils (Coleoptera: Curculionidae). Proc.
Entomol. Soc. Washington 89(1): 31-42.
SUTTON, R. A., G. SELHIME, AND W. MCCLOUD. 1972.
Colonization and release of Tetrastichus haitienisis
as a biological control agent for citrus root weevils. J.
Econ. Entomol. 65: 184-185.
SZABO, J. B. 1958. Erganzende Beobachtungen uber die
holarktische Gattung Fidiobia Ashmead 1894. Folia
Entomologica Hungarica 11: 457-464.
WOODRUFF, R. E. 1964. A Puerto Rican Weevil New to
the United States (Coleoptera: Curculionidae). Flor-
ida Department of Agriculture & Consumer Ser-
vices, Division of Plant Industry, Entomology
Circular (30):1-2, illus.
WOODRUFF, R. E. 1968. The Present Status of a West In-
dian Weevil (Diaprepes abbreviatus (L.)) in Florida.
Florida Department of Agriculture & Consumer Ser-
vices, Division of Plant Industry, Entomology Circu-
lar. No. 77, 4 p.


Florida Entomologist 88(1)







Virla et al.: Biology of Gonatocerus tuberculifemur


BIOLOGY OF GONATOCERUS TUBERCULIFEMUR (HYMENOPTERA:
MYMARIDAE), AN EGG PARASITOID OF THE SHARPSHOOTER,
TAPAJOSA RUBROMARGINATA (HEMIPTERA: CICADELLIDAE)


EDUARDO G. VIRLA1, GUILLERMO A. LOGARZO2, WALKER A. JONES3 AND SERGUEI TRIAPITSYN4
1CONICET-PROIMI, Avda Belgrano y Pasaje Caseros, T4001MVB, S. M. de Tucuman, Argentina

2USDA-ARS, South American Biological Control Laboratory, USDA-ARS SABCL
Agr. Couns. ARS Lab. U.S. Embassy Buenos Aires Unit 4325 APO AA 34034-0001

3Beneficial Insects Research Unit, ARS, USDA, 2413 E. Highway 83, Weslaco, TX 78596

4Entomology Research Museum, Department of Entomology, University of California, Riverside, CA 92521


ABSTRACT

Biological traits of a prospective candidate for biological control of the glassy-winged sharp-
shooter (GWSS), Homalodisca coagulata (Say) (Hemiptera: Cicadellidae), in the United
States are herein reported. The mymarid wasp, Gonatocerus tuberculifemur (Ogloblin), is an
egg-parasitoid native to Argentina and its first known host is Tapajosa rubromarginata (Sig-
noret), a species related to GWSS. Laboratory studies were made in Tucuman and Buenos
Aires Provinces, Argentina. Seven generations were maintained in the laboratory, and only
one adult emerged per host egg. The average parasitism rate was 71.6% of total eggs. Al-
though eggs of all ages (4 to 190 h old) were parasitized, wasps did not emerge from eggs over
96 h old. The percentage of wasp emergence was 66.5% from eggs between 4 and 72 h old.
Over the seven generations that G. tuberculifemur was reared, the parasitism rate ranged
between 55-84%. This percentage of emergence increased as the parasitoid generations pro-
gressed. The duration of development from oviposition to adult emergence of G. tuberculife-
mur was 12.6 1.8 days (range 11.4-13.0) at 22.5-27.5C and 70-80% RH. The duration of
development was significantly affected by sex and temperature. Males developed faster than
females (12.2 vs. 12.8, respectively).The sex ratio was not significantly different from 1:1.
Average adult longevity was 6.73 3.93 days fed on honey. Male and female longevity was
not significantly different. Oviposition and mating behavior are described.

Key Words: glassy-winged sharpshooter, Homalodisca coagulata, biological control, bionom-
ics, Gonatocerus, Mymaridae, egg parasitoid

RESUME

Se informan los resultados del studio de las caracteristicas biol6gicas de la avispa My-
maridae Gonatocerus tuberculifemur (Ogloblin), un parasitoide de huevos, native de Argen-
tina cuyo primer hospedador conocido es el sharpshooter Tapajosa rubromarginata
(Signoret). Esta avispa es un candidate potential para el control biol6gico de la chicharrita
de alas cristalinas, Homodalisca coagulata (Say) (Hemiptera: Cicadellidae) en los Estados
Unidos de Norteam6rica. Esta especie fue estudiada bajo condiciones de laboratorio en las
Provincias de Tucuman y Buenos Aires, Argentina. Siete generaciones fueron obtenidas, y
solo un adulto emergi6 de cada huevo parasitado. El porcentaje promedio de huevos parasi-
tados fue de 71.6%. A pesar que huevos de todas las edades testeadas (4-190 horas) fueron
atacados por hembras de G. tuberculifemur, no emergieron avispas de huevos con mas de 96
horas de edad. El porcentaje de emergencia de avispas fue 64.1%. Durante las siete genera-
ciones criadas el porcentaje de parasitsmo oscil6 entire 55 y 84% del total de huevos, este por-
centaje se increments con el advance de las generaciones. El tiempo necesario para completar
el desarrollo de G. tuberculifemur (desde huevo hasta adulto) fue de 12.6 1.8 dias (rango
11.4-13.0) a 22.5-27.5 C y 70-80% HR, y fue significativamente afectado por la temperature
y el sexo. Los machos necesitaron menos tiempo para desarrollar (12.2 dias) que las hembras
(12.8 dias). La proporci6n de sexos no mostr6 diferencias significativas. La longevidad de los
adults alimentados con miel fue de 6.73 3.93 dias, y no mostr6 diferencias significativas
entire los sexos. Se describe el comportamiento de oviposici6n y c6pula.


Translation provided by the authors.







Florida Entomologist 88(1)


Most of the Auchenorrhyncha (Hemiptera)
which are economically important to agriculture
are vectors of plant diseases such as viruses and
bacteria. The glassy-winged sharpshooter
(GWSS), Homalodisca coagulata Say (Hemiptera:
Cicadellidae: Proconiini), has recently become a
major pest in California, primarily as a vector of
Xylella fastidiosa Wells et al., which causes
Pierce's disease in grape vines and also infects
other crops. In California, wine and table grape
producers are under threat due to the action of
the GWSS in vectoring this pathogen. Biological
control is an important component in the man-
agement of the GWSS (Morgan et al. 2000; Jones
2001). In general, Cicadellidae are not infected by
pathogenic viruses, bacteria, and protozooa, how-
ever, they are infected by pathogenic fungi (Soper
1985). Waloff & Thompson (1980) and Denno &
Roderick (1990) found that mortality produced by
egg parasitoids was a "key factor" in Cicadellidae
species. These parasitoids are one of the few taxa
playing an important role in limiting leafhopper
populations (Ddbel & Denno 1993). Mymarid
wasps are the best-known egg parasitoids of leaf-
hoppers, and representatives of the family have
been successfully utilized in several instances for
the control of crop pests (Huber 1986; Meyerdirk
& Moratorio 1987).
The egg parasitoid, Gonatocerus tuberculife-
mur (Ogloblin), was found in several surveys for
egg parasitoids of Proconiini sharpshooters in Ar-
gentina during 2000-2004. Until 1986, 252 species
of Gonatocerus were known, with 60 described
from the Neotropics (Huber 1986). Of the 30 spe-
cies described from Argentina, only three have
known host records (De Santis 1957, 1979).
Few studies have been published on the bion-
omics of Gonatocerus (Miura 1979, 1990; Sahad
1982). There is no information on the bionomics of
G. tuberculifemur. We studied aspects of its biol-
ogy (egg-laying behavior, egg viability, duration of
developmental stages, sex ratio, and longevity)
reared under laboratory conditions on its natural
host, Tapajosa rubromarginata (Signoret).

MATERIALS AND METHODS

The studies were carried out in Planta Piloto de
Process Industriales Microbiol6gicos, CONICET,
San Miguel de Tucuman, Tucuman Province, and
at the USDA-ARS, South American Biological
Control Laboratory, Hurlingham, Buenos Aires
Province. Laboratory studies were conducted to
asses the effects of temperature on development
time, progeny sex ratio, adult longevity, oviposi-
tion, and mating behavior.

Parasitoid Culture

A culture of G. tuberculifemur was initiated in
the laboratory by collecting 20 egg masses of


T rubromarginata on Johnson grass, Sorghum
halepense (L.), in an open field in San Miguel de
Tucuman, Tucuman Province, in September 2002.
Additional collections were made when necessary.
The female Tapajosa rubromarginata lays her
eggs in parallel rows in groups of 3 to 32 eggs per
mass (n = 68, mean = 15.0; SD = 6.0) just under
the epidermis layer (E. G. V. unpublished data).
In the laboratory, field-collected (by sweeping)
females of T rubromarginata placed in polyeth-
ylen-terephtalathe (PET) cylindrical cages (35 cm
high x 18 cm diam.) on maize leaves were used to
obtain host eggs. Potted maize plants (pot of 6.3
dm3) in the vegetative stage (four to eight leaves)
were checked daily for eggs. When egg masses
were detected, the sharpshooters and the PET
cages were removed, and the corn leaf was intro-
duced into a 20-cm high x 2-cm diam glass tube
with 1-3 mated G. tuberculifemur females (24-48 h
old) for 24 h. Each glass tube top was fitted with a
cotton plug, which was moistened with water and
honey as needed. After five days, the parasitized
egg masses were removed from the leaf and trans-
ferred to a Petri dish with wet tissue paper and
covered with clear plastic food wrap to prevent des-
iccation, and to keep wasps from escaping. Parasit-
ized egg masses were checked daily to ensure leaf
quality until the emergence of the adult wasps.
Not all exposed eggs were parasitized, so to es-
timate percent parasitism, host eggs that
changed to brownish or reddish after five to seven
days were considered parasitizedd", while those
developing eyespots were considered "unparasit-
ized". The number of leafhopper nymphs and
wasps that emerged from the exposed eggs were
counted daily. Host age acceptability was studied
at six different ages: 4, 24, 48, 72, 96, and 190 h.
The total time required for the development
from egg to adult emergence, and progeny sex ra-
tios were measured at 4 temperatures: 22.5C
1.3, 24.5C + 1.3, 26.0C + 1.3, and 27.5C 1.3 in
875 individuals (457 males, 504 females) from
102 attacked egg masses. Differences in the dura-
tion of the development between male and
females were analyzed by a two-factor ANOVA.
Adult longevity was estimated based on the ob-
servation of 114 individuals (56 females and 58
males). Adults were kept individually in vials (7
cm length x 1 cm diameter) without host mate-
rial, but with honey for food. The experiment was
carried out under room temperature (22.9C
8C) at 70-80% RH with ambient natural light
providing, a summer photoperiod of approxi-
mately 15 L: 9 D. Differences between male and
females longevity were analyzed by a t test. The
effect of temperature on sex ratio was analyzed by
one-way ANOVA.
Voucher specimens were deposited in the ento-
mological collections of M. Lillo Institute (Tucu-
man, Argentina) and the University of California at
Riverside (Riverside, California, USA).


March 2005







Virla et al.: Biology of Gonatocerus tuberculifemur


RESULTS

Gonatocerus tuberculifemur is solitary, pro-
ducing only one adult per host egg. During the
study, 102 out of 142 egg masses exposed were at-
tacked, producing 961 wasps from 1500 parasit-
ized eggs out of 2095 exposed.
The average parasitism rate for all eggs was
71.6%; however, it differed according to egg age
(Table 1). Although eggs of all ages were parasit-
ized, wasps did not emerge from eggs aged 96-190
h old. The percentage of wasp emergence was
64.1% (from eggs between 4 and 72 h old). The
maximum percentage of wasp emergence was ob-
tained from 48-h-old eggs (71.5%). The average of
host nymph emergence for all egg ages was 12.2%;
increasing to 65.7% in eggs aged 190 h. No notice-
able effect of host egg age was observed on the sex
ratio, longevity, or on development time. Most of
the G. tuberculifemur adults emerged between
10:00 and 15:00 h. A similar observation was re-
ported by Sahad (1982) studying Gonatocerus sp.
attacking Nephotettix cincticeps Uhler in Japan.
Over seven generations (142 masses, 2095
eggs exposed), the parasitism rate ranged be-
tween 55-84%, and the emergence of wasps from
45 to 87% (Table 2). The emergence rate increased
over generations, from 58.5% during the first gen-
eration, to 86.3% for the seventh generation.
The immature stages of the parasitoid pro-
duced changes in the host egg. In the first three
days it was not possible to identify the parasitized
eggs through changes in coloration, except for
tiny dark oviposition marks in the leaf cuticle
and/or chorion. Host eggs containing parasitoid
larvae (2-5-days-old) had distinctive light brown
coloration. After 4-7 days, the whole egg became
orange or red. When the parasitoids reached the
pupal stage (6-12 days), it turned to dark brown
or black.
The duration of development from oviposition
to adult emergence of G. tuberculifemur was 12.6
+ 1.8 days (range 11.4-13.0). The duration of de-
velopment of G. tuberculifemur was influenced by
temperature (F = 32.130; df = 3, 861; P = 1.09E-
19), by sex (F = 21.082; df = 1, 861; P = 5.05E-06),


and by the interaction between temperature and
sex (F = 2,888; df = 3, 861; P = 0.03). Overall,
males developed faster than females (Table 3). At
22.5 and 24.5C, males did not show differences in
duration of development (Table 3). On the other
hand, duration of development of females was not
different at 26 and 27.5C. The sex ratio was
slightly female biased at 1.1: 1 (n = 504 females,
457 males), without being different (F = 2.308; df
= 3, 98; P = 0.0812).
Adult longevity was 6.73 3.93 days, showing
high variability. Few individuals were able to sur-
vive more than 15 days. There was no difference
in longevity by sex (Fig. 1) (t = -0.464; df = 1; P =
0.32). About 50% of the adults died on the 7th day.
Parasitoid mating behavior was observed as
follows. Immediately upon emergence, males
rushed for the females and mating occurred as
soon as they managed to reach the females and
position themselves appropriately. It was com-
mon to observe as many as 2-4 males around one
female. Each mating lasted 4-10 seconds. One
male was observed trying to mate with a female
while she was emerging.
No premating or preovipositional period was
observed; the oviposition of G. tuberculifemur be-
gan immediately after adult emergence. They
searched rapidly over the leaves, tapping the sur-
face constantly with the tips of the antennae on a
host egg mass. It was not determined whether
host location was by random search or by direc-
tional cues. However, females found the eggs very
quickly. Any time that a female was caged with a
plant containing an egg mass, the female located
the egg mass and began oviposition within 30 sec-
onds; this behavior was observed at least 30 times
when females were caged. The process of oviposi-
tion was initiated after the host was examined;
the female positioned the tip of the abdomen on
the host egg, the ovipositor was then extruded
and inserted through the leaf cuticle. As a general
behavior, once oviposition began, a female contin-
ued laying eggs on the remaining eggs in the
mass. The main cause of oviposition interference
was the arrival of another female at the egg mass;
as a consequence, one of them abandoned the egg


TABLE 1. EFFECT OF TAPAJOSARUBROMARGINATA EGG AGE ON PERCENT PARASITISM BY GONATOCERUS TUBERCULIFEMUR.

No eggs exposed No. parasitized No. emerged No. emerged
Egg age (hours) (no. masses) eggs (%) wasps (%) nymphs (%)

4 232(19) 121(52.7) 76(62.8) 51(22.0)
24 1222(74) 863(70.6) 578(67.0) 180(14.7)
48 394(29) 340(86.3) 243(71.5) 2(0.5)
72 158(15) 122(77.2) 64(52.5) 0(0.0)
96 54 (3) 51(94.4) 0 (0.0) 0 (0.0)
190 35(2) 3 (8.6) 0 (0.0) 23(65.7)
Total 2095 (142) 1500 (71.6) 961(64.1) 256 (12.2)







Florida Entomologist 88(1)


TABLE 2. NUMBER OF PARASITIZED EGGS AND WASP EMERGENCE OF GONATOCERUS TUBERCULIFEMUR OVER SEVEN
GENERATIONS REARED ON TAPAJOSA RUBROMARGINATA UNDER LABORATORY CONDITIONS.

No. egg No. eggs No. eggs No. wasps No. nymphs
Generation masses exposed parasitized (%) emerged (%) emerged(%)

I 30 447 359(80.3) 210(58.5) 36(8.1)
II 28 331 279(84.3) 137(49.1) 15(4.5)
III 19 338 186(55.0) 84(45.2) 42(12.4)
IV 19 241 183 (75.9) 126 (68.8) 4 (1.7)
V 10 151 104(68.9) 90(86.5) 27(17.9)
VI 21 238 178(74.8) 132(74.2) 40(16.8)
VII 15 349 211(60.5) 182(86.3) 92(26.4)


mass to continue looking for other egg masses in
the container. Superparasitism was observed in
the laboratory when 1 or 2 females were placed in
a container. In both cases, only one wasp emerged
from each egg.

DISCUSSION

Gonatocerus tuberculifemur can be considered
as proovigenic, due to its ability to deposit eggs
immediately after emergence (Flanders 1950).
This characteristic is shared with G. cincticipitis
Sahad (Miura 1990), and other members of the
Mymaridae (Clausen 1940). Tapajosa rubromargi-
nata is the first host recorded for this parasitoid.
The parasitism rate obtained in the laboratory
(71.6%) was much higher than that obtained for
Gonatocerus sp. (48.7%) parasitizing N. cincticeps
(Miura 1979). The percentage of parasitized eggs
that produced wasps (63.4%) was lower compared
to that obtained by Virla (2001) onAnagrus brevi-
phragma (80.5%), possibly due to differences in
the rearing methods used. In the present study,
egg masses were removed from the plant prior to
parasitoid emergence, whereas in Virla's study,
the host eggs were allowed to remain on the plant
until wasp emergence. Rotting or desiccation of
the eggs' host plant substrate leads to offspring
death (Sahad 1984). Better humidity control may
lead to higher wasp emergence rates.


Mymaridae show two behaviors regarding host
suitability: true egg parasitoids that can attack
and develop on newly laid eggs (before embryo de-
velopment), and those that attack eggs in all their
developmental stages. However, when eggs with
advanced embryos are attacked, only some spe-
cies are able to develop to the adult stage
(Clausen 1940; Waloff 1979; Chantarasa-ard &
Hirayima 1984). Gonatocerus tuberculifemur fe-
males were able to parasitize eggs of all develop-
ment stages, but wasps did not emerge when eggs
older than 96 h were attacked. Eggs older than 72
h were unsuitable for laboratory rearing and for
field collection of parasitoids as "sentinel" eggs.
Although parasitoid offspring cannot develop to
the adult stage in eggs with well-developed em-
bryos, the host egg is nevertheless killed. Further
research is needed to establish whether G. tuber-
culifemur can attack eggs with well-developed
embryos in the field.
The duration of development was significantly
different between males and females. For Gonato-
cerus sp., Miura (1979) found no differences be-
tween males and females. Virla (2001) reported
that sex affected development rate in Anagrus
sp., but Meyerdirk & Moratorio 1987 found no dif-
ferences in their studies with anotherAnagrus sp.
The observed ovipositional and mating behav-
iors, and the results for sex ratio and adult longev-
ity obtained in this study, were similar to those


TABLE 3. EFFECT OF THE TEMPERATURE AND SEX ON DURATION OF DEVELOPMENT OF GONATOCERUS TUBERCULIFE-
MUR UNDER LABORATORY CONDITIONS.

Males Females

Temperature (C)' n Mean (days) SD n Mean (days) SD

22.5 130 12.7 2.1 105 13.7 0.8
24.5 194 12.7 1.7 212 13.3 1.6
26.0 76 12.0 1.6 118 12.0 1.9
27.5 57 11.5 1.3 69 12.0 2.0
Overall mean 457 12.2 1.8 504 12.8 1.8

'The duration of the development was influenced by temperature (F = 32.130; df = 3, 861; P = 1.09E-19), by sex (F = 21.082; df
= 1, 861; P = 5.05E-06), and by the interaction between temperature and sex (F = 2,888; df= 3, 861; P = 0.03) (Two-way ANOVA).


March 2005







Virla et al.: Biology of Gonatocerus tuberculifemur


100oo cias Naturales y Museo, Notas del Museo, Tomo 19
w) R. No. 175: 129-144.
80 -0- female males DE SANTIS, L. 1979. Catalogo de los Himen6pteros Cal-
cidoideos de Am6rica al sur de los Estados Unidos.
T70 Comisi6n de Investigaci6n Cientifica de la Provincia
50 de Buenos Aires, Publicacion Especial, La Plata, Ar-
so gentina, 488 pp.
540 DOBEL, H., AND R. DENNO. 1993. Predator-planthopper
30 interactions, pp. 325-399 In R. Denno and T. Perfect
20 [eds.], Planthoppers, Their Ecology and Manage-
0o ment. Chapman & Hall, New York.
o FLANDERS, S. E. 1950. Regulation of ovulation and egg
l o 1 20 2S disposal in the parasitic Hymenoptera. Can. Ento-
mol. 82: 134-140.
HUBER, J. T. 1986. Systematics, biology and hosts of the
Fig. 1 Survival of males and females of Gonatocerus Mymaridae and Mymarommatidae (Insecta-Hy-
tuberculifemur. menoptera): 1758-1984. Entomography 4: 185-243.
JONES, W. A. 2001. Classical biological control of the
glassy-winged sharpshooter, pp. 50-51 In M. S. Hod-
dle [ed], California Conference on Biological Control
reported for other Gonatocerus and Anagrus spe- July 11-12, 2000. Riverside, CA.
cies (MacGill 1934; Clausen 1940; Miura 1979; MACGILL, E. 1934. On the biology of Anagrus atomus
Waloff 1979; Chantarasa-ard et al. 1984; Sahad (L.) Hal.: an egg parasite of the leafhopper Erythro-
1982, 1984; Meyerdirk & Moratorio 1987). neura pallidifrons Edwards. Parasitology 26: 57-63.
A culture of G. tuberculifemur has been suc- MEYERDIRK, D., AND M. MORATORIO. 1987: Biology of
.Anagrus giraulti (Hymenoptera: Mymaridae), an
cessfully maintained since March 2001 at the egg parasitoid of the beet leafhopper, Circulifer
USDA-APHIS Mission Texas quarantine labora- tenellus (Homoptera: Cicadellidae). Ann. Entomol.
tory with eggs of a factitious host, H. coagulata, Soc. Am. 80 (2): 272-277.
where the biology on this host egg is being stud- MIURA, T. 1979. On the longevity and parasitic activity of
ied. In the USDA-ARS SABCL and in the USDA- adult Gonatocerus sp. (Hymenoptera: Mymaridae).
APHIS Mission laboratories the parasitoid host Bull. Fac. Agric. Shimame Univ. 13: 156-162.
range is under study MIURA, K. 1990. Life-history parameters of Gonatocerus
cincticipitis Sahad (Hym. Mymaridae), an egg para-
sitoid of the green rice leafhopper, Nephotettix cincti-
ACKNOWLEDGMENTS ceps Uhler (Hom.-Cicadellidae). J. Appl. Entomol.
110 (4): 353-357.
We thank Laura Varone, Ver6nica Manrique (USDA- MORGAN, D. J. W., S. V. TRIPITSYN, R. A. REDAK, L. G.
ARS South American Biological Control Laboratory, BEZARK, AND M. S. HODDLE. 2000. Biological control
Hurlingham, Buenos Aires, Argentina), and Erica Luft of the glassy-winged sharpshooter: current status
and Eduardo Frias (PROIMI, secci6n Control Biol6gico) and future potential, pp. 167-171 In M. S. Hoddle
for assistance in the laboratory and the field, and two [ed.], California Conference on Biological Control
anonymous reviewers for thoughtful comments on the July 11-12, 2000. Riverside, CA.
manuscript. SAHAD, K. 1982. Biology and morphology of Gonatocerus
sp. (Hymenoptera, Mymaridae), an egg parasitoid of
REFERENCES CITED the green rice leafhopper, Nephotettix cincticeps
Uhler (Homoptera, Deltocephalidae). I. Biology.
CHANTARASA-ARD, S., AND Y. HIRAYIMA. 1984. Host Kontyu 50: 246-260.
range and host suitability of Anagrus incarnatus SAHAD, K. A. 1984. Biology of Anagrus optabilis (Per-
Haliday (Hymenop.: Mymaridae), an egg parasitoid kins) (Hymenoptera-Mymaridae), an egg parasitoid
of delphacid planthoppers. Appl. Entomol. Zool. 19: of delphacid planthoppers. Esakia 22: 129-144.
491-497. SOPER, R. 1985: Pathogens of leafhoppers and plant-
CHANTARASA-ARD, S., Y. HIRAYIMA, AND T. MIURA. 1984. hoppers, pp. 469-488 In L. Nault and J. Rodriguez [ed.],
Ecological studies on Anagrus incarnatus Haliday The Leafhoppers and Planthoppers. Wiley, New York.
(Hymenop.: Mymaridae), an egg parasitoid of the VIRLA, E. G. 2001. Notes on the biology of Anagrus
rice planthoppers. I. Functional response to host breuiphragma (Hymenoptera-Mymaridae), natural
density and mutual interference. J. Fac. Agric., Kyu- enemie of the corn leafhopper Dalbulus maidis
shu Univ. 29 (1): 59-66. (Hemiptera-Cicadellidae) and others plant diseases
CLAUSEN, C. 1940. Entomophagous Insects. McGraw-Hill vectors in South America. Bol. Sanidad Vegetal "P1-
Publications in Zoological Sciences, New York. 687 pp. agas", Madrid-Spain 27: 239-247.
DENNO, R. F., AND G. RODERICK. 1990. Population biol- WALOFF, N. 1979. Studies on grassland leafhoppers and
ogy of planthoppers. Annu. Review of Entomol. 35: their natural enemies. Adv. Ecol. Res. 11: 81-215.
489-520. WALOFF, N., AND P. THOMPSON. 1980: Census data and
DE SANTIS, L. 1957. Descripci6n de nuevos g6neros yes- analysis of populations of some leafhoppers
species de calcidoideos argentinos, II (Hymenoptera). (Auchenorrhyncha: Homoptera) of acidic grassland.
Universidad Nacional de La Plata, Facultad de Cien- J. Anim. Ecol. 49: 395-416.







Florida Entomologist 88(1)


March 2005


COMPARISON OF BEETLE DIVERSITY AND INCIDENCE OF PARASITISM
IN DIABROTICINA (COLEOPTERA: CHRYSOMELIDAE) SPECIES
COLLECTED ON CUCURBITS

SAGRARIO GAMEZ-VIRUES AND ASTRID EBEN
Departamento de Ecologia Funcional, Instituto de Ecologia, A.C. Apartado Postal 63
CP 91070 Xalapa, Veracruz, M6xico

ABSTRACT

Diabroticina (Chrysomelidae: Galerucinae: Luperini) beetles were sampled under field con-
ditions on two host plants of the family Cucurbitaceae, Cucurbita okeechobeensis ssp. mar-
tinezii L. Bailey (bitter, wild cucurbit) and C. moschata (Lam.) Poiret (non bitter, cultivated
cucurbit). Seventeen species of Diabroticina were collected. Acalymma blomorum Munroe &
Smith was the most abundant species on both host plants. The only parasitoid found was Ce-
latoria compressa Wulp (Diptera: Tachinidae). This parasitoid attacked more beetle species
on the cultivated cucurbit (65%) than on the bitter cucurbit (20%). However, the percentages
of parasitism observed in all species were low (0.4% to 12.5%). These data suggest that host
plant species might have an effect on parasitism.

Key Words: Acalymma, Celatoria compressa, Cucurbita okeechobeensis ssp. martinezii, Cu-
curbita moschata, host plant association, Diabroticina beetles

RESUME

Diecisiete species de Diabroticina (Chrysomelidae: Galerucinae: Luperini) fueron colecta-
das en dos plants hospederas de la familiar Cucurbitaceae, Cucurbita okeechobeensis ssp.
martinezii L. Bailey (amarga, silvestre) y C. moschata (Lam.) Poiret (no amarga, cultivada).
Acalymma blomorum Munroe & Smith fue la especie mas abundante en ambas hospederas.
Se obtuvo unicamente el parasitoide Celatoria compressa Wulp (Diptera: Tachinidae) sobre
las poblaciones de Diabroticina. Este parasitoide atac6 mayor numero de species de escar-
abajos en la calabaza cultivada (65%) que en la calabaza amarga (20%). Los porcentajes de
parasitismo observados se consideraron bajos (0.4% a 12.5%). Los datos sugieren que las
plants hospederas pudieron haber tenido un efecto sobre el parasitoide.

Translation provided by authors.


Diabroticina (Chrysomelidae: Galerucinae:
Luperini) are native to Mexico and Central Amer-
ica (Webster 1895). Few data, however, are pub-
lished on host plant associations (Eben &
Espinosa de los Monteros 2003) and natural ene-
mies from this area (Eben & Barbercheck 1996).
In the Diabroticites (subtribe Diabroticina),
the association of a number of species with plants
in the family Cucurbitaceae is a well-known ex-
ample for the effect of plant secondary chemistry
on a plant-insect interaction (Chambliss & Jones
1966; Howe et al. 1976; Metcalf et al. 1982; Met-
calf 1986). Host preferences of Diabroticites are
strongly influenced by the presence of cucurbit-
acins (tetracyclic triterpenoids) in many wild cu-
curbit hosts. These non-volatile secondary
compounds act as arrestants and feeding stimu-
lants for these beetles (Chambliss & Jones 1966;
Metcalf & Lampman 1989).
Furthermore, it has been proposed that Di-
abroticina species sequester cucurbitacins for
their chemical defense. Studies of tritrophic ef-
fects demonstrated that cucurbitacins are deter-
rents for natural enemies such as mantids


(Ferguson & Metcalf 1985), passerine birds
(Nishida & Fukami 1990), the pathogenic fungus
Metarhizium anisopliae (Moniliales: Monilia-
ceae) (Tallamy et al. 1998), and entomopatho-
genic nematodes (Barbercheck et al. 1995). On
the other hand, no negative effects on general
predators such as carabid larvae, mites, and cen-
tipedes (Brust & Barbercheck 1992) have been
found. To date, no clear pattern has emerged from
these studies. Field studies on larval host associ-
ations in the natural habitat are difficult due to
the fact that Diabroticina larvae are root feeders.
Interestingly, although parasitoids are inti-
mately associated with their hosts, and third
trophic level effects of plant secondary com-
pounds are described for a number of plant-insect
associations (Gauld et al. 1992; Rowell-Rahier et
al. 1995;Agrawal et al. 2002), no data exist for the
cucurbit/Diabroticina/parasitoid system.
The objective of the present field study was to
compare beetle abundance and diversity on two
Cucurbita spp. that differed in presence, Cucurb-
ita okeechobeensis ssp. martinezii L. Bailey, or ab-
sence, C. moschata (Lam.) Poiret, of secondary







Gamez & Eben: Diversity and Parasitism of Diabroticinas


compounds. Both cucurbits, the bitter Cucurbita
o. martinezii and the cultivated C. moschata, are
the most common cucurbits in the study area.
Their morphology is similar, but the bitter species
has smaller and paler flowers, and smaller leaves.
Furthermore, the bitter species produces second-
ary compounds characteristic for Cucurbitaceae,
the cucurbitacins (Metcalf et al. 1982; R. Ventura,
unpubl. data). Moreover, parasitoid incidence in
adult beetles was monitored and compared be-
tween individuals collected from the two host
plants.

MATERIAL AND METHODS

Study Area and Host Plants

All adult insects were collected in the central
zone of the state of Veracruz, Mexico. Mean an-
nual temperature fluctuates between 18 and 25C,
with three distinct seasons: a dry-cool season (No-
vember-March), a dry-warm season (April-May)
and a wet-warm season (June-October). Annual
rainfall varies between 800 and 2500 mm, with a
peak in the second warm season (Soto & Garcia
1989). Common crops in the area are sugarcane,
coffee, corn, squash, and beans. The original vege-
tation at lower altitudes is deciduous forest,
whereas remnants of tropical cloud forest are
found at higher altitudes (G6mez-Pompa 1977).
Within the study area, six locations for each
Cucurbita spp. were identified. These locations
were separated by at least nine km (i.e., 12 sam-
ple areas in total). They differed in altitude and
climatic conditions (Table 1). To avoid collections
of beetles which might recently have moved be-
tween hosts, sites with coexistence of both cucur-
bits were not accepted. Due to the fact that beetle
abundance is affected by the presence of flowers
(pers. observe) insects were collected once or twice
per week on flowering plants only. When plants
began to dry out, they were replaced by others in
flowering stage within the same area. At each col-
lection date we recorded the diversity and abun-
dance of beetles found on both plants.
Areas of approximately 100 m2 covered by cu-
curbit vines were measured at each location to de-
fine the collection site.


Beetle Collection

Beetles were collected from August to Decem-
ber 2001 and from May to November 2002. Collec-
tion dates were based on previous studies
(Rodriguez & Magallanes 1994; Eben & Bar-
bercheck 1996; Cabrera & Cabrera 2004) which
found a clear seasonality for Diabroticinas with
peak abundance from early summer to fall.
Plants were visually inspected for Diabroticina
adults. The sampling unit was the number of bee-
tles collected per person in one hour. Field col-
lected adults were separated by species, location,
and collection date. In order to allow for parasi-
toid emergence, the colonies of adult field col-
lected beetles were maintained in the laboratory
(25 + 3C), with a photoperiod of 13:11 (L:D), in
transparent plastic containers (15 cm diameter x
25 cm length), with a gaze cover for ventilation.
Beetles were fed fruits of Cucurbita pepo L. (zuc-
chini) and artificial diet (Branson et al. 1975).
Abundance of Diabroticina were analyzed by one-
way ANOVA (P < 0.05) with SigmaStatTM statisti-
cal software version 2.0 (Jandel Scientific 1992-
1997), after square root transformation.

Parasitism Rates

All cages with beetles were checked daily to
collect and count parasitoid pupae (Eben & Bar-
bercheck 1996). In addition, dead beetles with an
entire abdomen were dissected to determine pres-
ence or absence of immature parasitoids. Percent-
age parasitism was calculated as the number of
immature and adult parasitoids obtained for the
total number of each beetle species, date, and lo-
cation. Data were analyzed by a chi-square test
(Zar 1999). Correlation between beetle abun-
dance and percentage parasitism was analyzed
by linear regression (Zar 1999).

RESULTS

In the study area, C. moschata is cultivated for
human consumption. For this reason it was com-
monly found along road sides and in mixed corn-
squash plots, mostly in direct sunlight. Cucurbita
o. martinezii is grown in shadier places, with oth-


TABLE 1. CLIMATIC ZONES OF THE SIX COLLECTIONS AREAS IN THE STATE OF VERACRUZ.

Mean annual Mean annual
Area Altitude (m) temperature (C) precipitation (mm) Geographical location

Coatepec 1200 19.2 1926.0 1927'N/9658'W
Jalcomulco 340 24.0 1125.0 1920'N/9646'W
Naolinco 1540 16.0 1639.7 1939'N/9652'W
Teocelo 1160 18.1 1797.0 1939'N/9658'W
Tlalnelhuayocan 1640 18.0 1009.0 1939'N/9658'W
Xalapa 1460 18.0 1509.1 1932'N/9655'W







Florida Entomologist 88(1)


ers plants as climbing structures. It was most
abundant in and around coffee plantations.
We found 17 species of Diabroticinas from five
genera (Table 2). All species were collected from
C. moschata, 15 species were collected from C. o.
martinezii. The abundance of three species, A blo-
morum, D. balteata, and I. tetraspilota, differed
between both cucurbit hosts (P = 3.5 x 109, P =
0.0011, and P = 0.048, respectively). The other 12
beetle species were not more abundant in any of the
two host plants. Proportions of all species were dif-
ferent in the two cucurbits. In C. moschata, Aca-
lymma blomorum was the most abundant beetle
species, followed by Diabrotica balteata, D. scutel-
lata, and D. viridula, and in C. o. martinezii, Isotes
tetraspilota, A. fairmairei, and D. scutellata.
The most diverse genus was Diabrotica with six
species in the fucata group, D. balteata, D. dissi-
milis, D. nummularis, D. sexmaculata, D. tibialis,
D. undecimpunctata duodecimnotata, and three
species in the virgifera group: D. porracea, D. scutel-
lata, and D. viridula. Diabrotica balteata and
D. scutellata were the most abundant species
within either group. Cerotoma atrofasciata, Gynan-
drobrotica lepida and G. nigrofasciata were most
common on the foliage of C. moschata (Table 2).


Incidence of Parasitism

The only parasitoid found was a tachinid spe-
cies, Celatoria compressa Wulp. Parasitoids were
obtained in June and July 2002 from beetles col-
lected on the bitter cucurbit. No parasitoids were
found in beetles collected on this plant in 2001. In
beetles collected on the cultivated cucurbit, para-
sitoids were present throughout the collecting pe-
riod in both years. In general, parasitoid pupae
were obtained during the first 48 h after collect-
ing the host beetle. Adult parasitoids emerged
from all parasitoid pupae (n = 169). The presence
of other parasitoids was not observed.
The tachinid parasitoid was found in three of
the 15 beetle species collected on the bitter cucur-
bit (20%), and in 11 of the 17 beetle species col-
lected on the cultivated cucurbit (65%). On the
bitter cucurbit, the parasitoid attackedA. blomo-
rum,A. fairmairei, and D. balteata at percentages
of 0.9%, 7.7%, and 5%, respectively (Table 2). In
the species collected on the cultivated cucurbit,
A. blomorum, A. fairmairei,A. innubum, C. atrofa-
sciata, D. balteata, D. porracea, D. scutellata,
D. sexmaculata, D. tibialis, D. viridula, and G. ni-
grofasciata were parasitized. The percentage of


TABLE 2. DIABROTICINA BEETLE ABUNDANCE COLLECTED ON CUCURBITA OKEECHOBEENSIS SSP. MARTINEZII (A) AND
C. MOSCHATA; (B) (MEAN BEETLES COLLECTED PER PERSON PER HOUR), AND PERCENTAGE PARASITISM IN
THE TOTAL NUMBER COLLECTED OF EACH BEETLE SPECIES IN THE YEARS 2001 AND 2002.

2001 2002

Mean % Mean %

Species A B A B A B A B

Acalymma blomorum Munroe & Smith* 3.83 50.1 0 3.7 8.17 57.71 0.9 0.6
A. fairmairei (Fabricius) 3.61 4.29 0 0.4 2.31 1.99 7.7 0.7
A. innubum (Fabricius) 0.33 5.19 0 0.8 0.15 5.78 0 0
A. triuittatum Mannerheim 0.5 2.33 0 0 0.04 3.22 0 0
Diabrotica group fucata
D. balteata LeConte* 1.11 0.61 0 0 0.44 35.1 5 3.7
D. dissimilis Jacoby 0 0.04 0 0 0 0.02 0 0
D. nummularis Harold 0.11 0.74 0 0 0.02 0.09 0 0
D. sexmaculata Baly 0 0.22 0 0 0.19 0.31 0 5.9
D. tibialis Baly 0.11 0.72 0 0 0.58 14.11 0 4.6
Diabrotica group virgifera
D. porracea Harold 0.5 0.24 0 0 0.23 1.81 0 2.5
D. scutellata Baly 1.65 5.54 0 1.4 3.15 1.78 0 0.8
D. undecimpunctata duocecimnotata Harold 0.39 0.06 0 0 0.08 0.01 0 0
D. viridula (Fabricius) 0.11 0.37 0 0 0.15 5.4 0 0.2
Cerotoma atrofasciata Jacoby 0 0.28 0 12.5 0.83 3.33 0 2.5
Gynandrobrotica lepida (Say) 0 0.83 0 0 0.02 0.31 0 0
G. nigrofasciata (Say) 0 1.53 0 2.5 0 0.02 0 0
Isotes tetraspilota Baly* 0.44 0.03 0 0 8.56 0.01 0 0

*Significant differences between abundance per cucurbit (P < 0.05), and 0: No beetles nor parasitoids were found.


March 2005







Gamez & Eben: Diversity and Parasitism of Diabroticinas


parasitism in these species varied between 0.4%
and 12.5% (Table 2). Highest percentages of par-
asitism were found in C. atrofasciata. No signifi-
cant differences in parasitism between beetle
species were detected. Also, no correlation be-
tween beetle abundance and percentage parasit-
ism was found. We found, however, significantly
higher numbers of parasitoids in beetles collected
on the cultivated cucurbit (X2(1, 005 = 6.46). During
the present study, parasitism was not observed in
A. trivittatum, D. dissimilis, D. nummularis, G. lep-
ida, and I. tetraspilota.

DISCUSSION

The diversity of Diabroticina species on C. o.
martinezii and C. moschata was similar. Never-
theless, Diabrotica scutellata and Isotes tetraspi-
lota were more abundant on bitter C. o. martinezii,
whereas Acalymma blomorum and D. balteata
were more abundant on the cultivated C. moschata.
Acalymma blomorum was the most abundant spe-
cies in both Cucurbita spp. These results are sim-
ilar to data obtained by Cabrera & Cabrera (2004)
with respect to the abundance ofAcalymma spp.
in Cucurbitaceae in Argentina. Within the fucata
group, D. balteata was the most abundant species,
and within the virgifera group D. scutellata was
dominant. These results agreed with data re-
ported by Rodriguez & Magallanes (1994) for
D. balteata in Tamaulipas and Veracruz, and by
Eben & Barbercheck (1996) forD. scutellata in Ve-
racruz. In the present study, Diabrotica dissimilis
and G. nigrofasciata were not collected on the bit-
ter cucurbit. The other 12 species had a continu-
ously low abundance on both cucurbits.
Acalymma blomorum and D. balteata were col-
lected most frequently in C. moschata, perhaps as
a result of the high quantities of pollen in this cu-
curbit. We observed that the beetles visited these
plants to feed on petals and flowers. Isotes tetra-
spilota was the only species that was found feed-
ing on the leaves of C. o. martinezii, and it was
never seen on the cultivated cucurbit C. moschata.
Acalymma blomorum, A. fairmairei, C. atrofasci-
ata, and D. balteata were found on the cultivated
cucurbit even when the plants began to dry. Gynan-
drobrotica nigrofasciata was collected only in
2001 on the cultivated cucurbit and furthermore,
in much higher numbers, on a leguminous plant
(Pachyrhizus erosus (L.) Urban) growing in the vi-
cinity. Fabaceae are reported as host family for
this genus (Jolivet & Hawkeswood 1995).
Celatoria compressa was the only parasitoid
species obtained. It was reported for the first time
by Eben & Barbercheck (1996) in Diabroticite
beetles. Previously, Celatoria bosqi Blanch. (Hei-
neck-Leonel & Salles 1997) C. diabroticae Shimer
and C. crawii Coquillett had been collected from
some Diabrotica spp. (Chittenden 1905; Sell
1915; Gordon et al. 1987) andA. vittatum (Walton


1914). The differences in parasitism in the species
collected on both cucurbits, three species in C. o.
martinezii vs. 11 species in C. moschata, were no-
table and might suggest that floral odor, or sec-
ondary compounds sequestered by beetles from
the bitter host plant, had an effect on the adult
parasitoid. To date, no study has tried to corrobo-
rate this for parasitoids of Diabroticina beetles.
On the other hand, Diabroticina beetles were
more abundant on the flowers and leaves of
C. moschata, perhaps because this species offered
greater amounts of pollen than C. o. martinezii.
Consequently, C. compressa might have simply
responded to the abundance of host insects in
C. moschata. In general, the incidence of the ta-
chinid in the guild of beetle species collected in
both cucurbits was low, with parasitism ranging
from 0.4% to 12.5%. In an earlier study similar
parasitism rates of 1.0% to 11.1% were found
(Eben & Barbercheck 1996). Parasitism by
C. bosqi in D. speciosa ranged from 0.1 to 30.2%
(Heineck-Leonel & Salles 1997) and C. diabroti-
cae parasitized D. u. howardi with rates of 3 to
15% (Meinke & Gould 1987; Elsey 1988).
Given our observations, it would be interesting
to investigate if cucurbitacins sequestered by the
beetles collected on C. o. martinezii function as a
repellent for C. compressa. Our data suggest that
a possible effect of plant secondary compounds is
stronger on adult parasitoid behavior (i.e., host
acceptance) than on immature physiology, since
all parasitoid larvae that closed from beetles pu-
pated and developed successfully into adults.
During the course of our study a larger number
of isolated plants of the cultivated than the bitter
cucurbit species was found. This situation was
contrary to our observations in previous years. It
might be the consequence of the rapidly declining
number of coffee plantations in the central area of
Veracruz. In this area, the main habitat of C. o.
martinezii are coffee plantations, where it is
found growing in a vertical fashion upon the cof-
fee bushes as climbing structures. By contrast,
C. moschata grows horizontally, covering bare ar-
eas exposed to plain sunlight. These differences in
habitat and microclimate might have influenced
the abundance and species composition of Diabro-
ticina beetles present in both plants as well as the
searching behavior of C. compressa.

ACKNOWLEDGMENTS
Thanks to A. Martinez who helped with the statisti-
cal analysis. R. Ventura assisted with collections and
maintenance of colonies. This study was financed by
project CONACYT 35501-Vto A. Eben and partially with
the assistanship CONACYT 162421 to S. Gamez-Viruis.

REFERENCES CITED
AGRAWAL, A., A. JANSSEN, J. BRAUIN, M. A. POSTHUMOUS,
AND M. W. SABELIS. 2002. An ecological cost of plant











defense: attractiveness of bitter cucumber plants to
natural enemies of herbivores. Ecology Letters 5:
337-385.
BARBERCHECK, M. E., J. WANG, AND I. S. HIRSH. 1995.
Host plant effects on entomopathogenic nematodes.
J. Invertebr. Pathol. 66: 141-145.
BRANSON, T. F., P. L. GUESS, J. L. KRYSAN, AND G. R.
SUTTER 1975. Corn rootworms: laboratory rearing
and manipulation. Agric. Res. Serv. Bull. NC-28.
BRUST, G. E., AND M. E. BARBERCHECK. 1992. Effect of
dietary cucurbitacins C on southern corn rootworm
(Coleoptera: Chrysomelidae) egg survival. Environ.
Entomol. 21: 1466-1471.
CABRERA-WALSH, G., AND N. CABRERA. 2004. Distribu-
tion and hosts of the pestiferous and other common
Diabroticites from Argentina and Southern South
America: a geographic and systematic view, pp. 333-
350 In P. H. Jolivet, J. A. Santiago-Blay, and M.
Schmitt [eds.], New Developments in the Biology of
Chrysomelidae. SPB Academic Publishers, The
Hague, Netherlands.
CHAMBLISS, O. L., AND C. M. JONES. 1966. Cucurbit-
acins: specific insect attractants in Cucurbitaceae.
Science 153: 1392-1393.
CHITTENDEN, F. H. 1905. Notes on the cucumber bee-
tles. U.S. Dept. Agric. Bur. Entomol. Bull. 82: 67-75.
EBEN, A., AND M. E. BARBERCHECK. 1996. Field obser-
vations on host plant associations and natural ene-
mies of Diabroticite beetles (Chrysomelidae:
Luperini) in Veracruz, Mexico. Act. Zool. Mexicana
(n.s.) 67: 47-65.
EBEN, A., AND A. ESPINOSA DE LOS MONTEROS. 2003.
Evolution of host plant breadth in Diabroticites (Co-
leoptera: Chrysomelidae), pp. 175-182 In D. G. Furth
[ed.], Special Topics in Leaf Beetles Biology. Proc.
5th Int. Sym. on the Chrysomelidae. Pensoft Pub-
lishers, Sofia, Moscow. 300 pp.
ELSEY, K. 1988. Cucumber beetle seasonality in coastal
South Carolina. Environ. Entomol. 17: 495-502.
FERGUSON, J. E., AND R. L. METCALF. 1985. Cucurbit-
acins: plant-derived defense compounds for diabro-
ticites (Coleoptera: Chrysomelidae). J. Chem. Ecol.
11(3): 311-318.
GAULD I., K. J. GASTON, AND D. H. JANZEN. 1992. Plant
allelochemicals, tritrophic interactions and the
anomalous diversity of tropical parasitoids: the
"nasty" host hypothesis. Oikos. 65: 353:357.
G6MEZ-POMPA, A. 1977. Ecologia de la Vegetaci6n del
Estado de Veracruz. Compafia Editorial Continen-
tal, S. A. M6xico. 91 pp.
GORDON, R., J. ELLINGTON, G. F. FAUBION, AND H. GRA-
HAM. 1987. A survey of the insect parasitoids from
alfalfa and associated weeds in New Mexico. South-
west. Entomol. 12: 335-351.
HEINECK-LEONEL, M. A., AND L. A. B. SALES. 1997. In-
cidence of parasitoids and pathogens in adults of
Diabrotica speciosa (Germar) (Coleoptera: Chryso-
melidae) in Pelotas, R. S. Anais Soc. Entomol. Brasil
26:81-85.


March 2005


HOWE, W. L., J. R. SANBORN, AND A. M. RHODES. 1976.
Western corn rootworm adult and spotted cucumber
beetle associations with Cucurbita and cucurbit-
acins. Environ. Entomol. 5: 1043-1048.
JOLIVET, P., AND T. J. HAWKESWOOD. 1995. Host-plants
of Chrysomelidae of the World. Backhuys Publish-
ers, Leiden. 281 pp.
MEINKE, L. J., AND F. GOULD. 1987. Thermoregulation
by Diabrotica undecimpunctata howardi and poten-
tial effects on overwintering biology. Entomol. exp.
Appl. 45: 115-122.
METCALF, R. L. 1986. Coevolutionary adaptations of
rootworm beetles to cucurbitacins. J. Chem. Ecol. 12:
1109-1124.
METCALF, R. L., AND R. L. LAMPMAN. 1989. The chemi-
cal ecology of Diabroticites and Cucurbitaceae. Ex-
perientia 45: 240-247.
METCALF, R. L., A. M. RHODES, R. A. METCALF, J. FERGU-
SON, E. R. METCALF, AND P. Y. LU. 1982. Cucurbitacin
content and Diabroticite (Coleoptera: Chrysomelidae)
feeding upon Cucurbita spp. Environ. Entomol. 11:
931-937.
NISHIDA, R., AND H. FUKAMI. 1990. Sequestration of dis-
tasteful compounds by some pharmacophagous in-
sects. J. Chem. Ecol. 16(1): 151-164.
RODRIGUEZ-DEL-BOSQUE, L. A., AND A. MAGALLANES-
ESTALA. 1994. Seasonal abundance of Diabrotica
balteata and other Diabroticite beetles (Coleoptera:
Chrysomelidae) in northeastern Mexico. Environ.
Entomol. 23: 1409-1415.
ROWELL-RAHIER, M., J. M. PASTEELS, A. ALONSO-
MEJiA, AND L. P. BROWES. 1995. Relative unpalatabil-
ity of leaf beetles with either biosynthesized or seques-
tered classical defense. Anim. Behav. 49: 709-714.
SELL, R. A. 1915. Some notes on the western twelve-
spotted and the western striped cucumber beetle. J.
Econ. Entomol. 8: 515-520.
SOTO, E. M., AND E. GARCIA. 1989. Atlas Climatico del
Estado de Veracruz. Institute de Ecologia, Xalapa,
Ver, M6xico. 125 pp.
TALLAMY. D. W., D. P. WHITTINGTON, F. DEFURIO, D. A.
FONTAINE, P. M. GORSKI, AND P. W. GOTHRO. 1998.
Sequestered cucurbitacins and pathogenicity of
Metarhizium anisopliae (Moniliales: Moniliaceae) on
spotted cucumber beetle eggs and larvae (Coleoptera:
Chrysomelidae). Environ. Entomol. 27(2): 366-372.
VENTURA PEREZ, R. I. 2002. Aislamiento e identificaci6n
por RMN de cucurbitacinas a partir de Cucurbita
martinezii (Cucurbitaceae) y determinaci6n cuali-
tiva en Chrysomelidae. Unpubl. Bachelor thesis,
Universidad Veracruzana, Xalapa.
WALTON, W. R. 1914. A new tachinid parasite of Dia-
brotica vittata. Proc. Entomol. Soc. Washington 16:
11-13.
WEBSTER, F. M. 1895. On the probable origin, develop-
ment and diffusion of North American species of ge-
nus Diabrotica. J. N. Y. Entomol. Soc. 3: 158-166.
ZAR, J. H. 1999. Biostatiscal Analysis. 4th ed. Prentice-
Hall, NJ. 663 pp.


Florida Entomologist 88(1)







Amalin et al.: Influences on Parasitism by C. etiennei


EFFECTS OF HOST AGE, FEMALE PARASITOID AGE,
AND HOST PLANT ON PARASITISM OF CERATOGRAMMA ETIENNEI
(HYMENOPTERA: TRICHOGRAMMATIDAE)


DIVINA M. AMALIN1, JORGE E. PENA AND RITA E. DUNCAN
University of Florida, Tropical REC, IFAS, Department of Entomology and Nematology
18905 SW 280th St., Homestead, FL 33031

'Current Address: USDA-APHIS, 13601 Old Cutler Rd., Miami, FL 33158

ABSTRACT

Parasitism of Diaprepes abbreviatus (L.) eggs by Ceratogramma etiennei Delvare as influ-
enced by host age, age of the female parasitoid, and host plant preference was evaluated un-
der laboratory or greenhouse tests. Percent parasitism of D. abbreviatus eggs by C. etiennei
decreased as eggs matured. The optimal age of C. etiennei for successful parasitism ranged
from 1-2-d old. Host plant leaf thickness, leaf pubescence, and plant strata probably played
a role on the parasitism by C. etiennei. This parasitoid is diurnal and spent approximately 5
min searching for eggs laid in cryptic locations, 46 min parasitizing an egg mass and 24 min
resting. This biological information is relevant in evaluating the potential of C. etiennei in
the classical biological control of D. abbreviatus.

Key Words: parasitism, Ceratogramma etiennei, Diaprepes abbreviatus, host age, parasitoid
age, host plants, host preference, host-finding behavior

RESUME

Se estudi6 el efecto de edad del hospedero, edad del parasitoide, y preferencia del parasitoide
a la plant hu6sped en el parasitismo exitoso de Ceratogramma etiennei Delvare sobre hue-
vos del picudo Diaprepes abbreviatus (L.). El porcentaje de parasitismo disminuy6 al incre-
mentar la edad de la postura. La edad 6ptima de C. etiennei para realizar un parasitismo
exitoso es 1-2 d de edad. Ceratogramma etiennei demostr6 cierta preferencia a la plant
huesped en terminos de grosor de la lamina foliar, pubescencia de hojas y estrato de la plant
donde se encuentren las posturas de D. abbreviatus. Ceratogramma etiennei es diurna y
gasta aproximadamante 5 minutes buscando las posturas, 46 min parasitizando y 26 min
descansando. La informaci6n generada durante este studio puede ayudar a evaluar el po-
tencial de C. etiennei como agent de control biol6gico de D. abbreviatus.


Translation provided by the authors.


The Diaprepes root weevil, Diaprepes abbre-
viatus (L.), is one of the major pests of citrus, veg-
etables, and ornamentals in Florida, Puerto Rico,
and the West Indies (Beavers et al. 1983; Figueroa
& Roman 1990; Sirjusingh et al. 1992).Diaprepes
abbreviatus adults feed on the foliage of many
plant species belonging to at least 30 families
(Simpson et al. 1996;Adair et al. 1998). After mat-
ing, the females deposit their eggs between host
plant leaves glued together with an adhesive pro-
duced by the female (Richman et al. 1983). The
eggs hatch in 7-10 d and the larvae drop to the
surface of the ground and feed on the roots of most
host plants (Woodruff 1964; Whitcomb et al.
1982). A lack of native parasitoids attacking this
weevil in Florida (Hall et al. 2001) and past fail-
ures to establish exotic parasitoids against this
weevil (Beavers et al. 1980), justify further efforts
to introduce, release, and evaluate candidate par-


asitoids for Florida (Peia et al. 1998; Peia &
Amalin 2000). One of these candidates is Cerato-
gramma etiennei Delvare (Hymenoptera: Tricho-
grammatidae), a highly specific parasitoid to
Diaprepes in Guadeloupe (Etienne et al. 1990). It
was introduced into Florida from Guadeloupe in
1997 (Peia et al. 1998) and released from 1998-
2000 in citrus, ornamental fields, and natural
habitats infested withD. abbreviatus. Subsequent
to release, C. etiennei was recovered from lime,
Citrus aurantifolia (Christman) Swingle, and
pigmy palms, Phoenix roebelenii O'Brien in south
Florida (Table 1). However, none were recovered
from 2001-2002 in the same locations. The reason
for its disappearance is unknown.
This paper provides some of the information
that may be involved in the host selection process
by C. etiennei, such as host age, age of the parasi-
toids, and host plant preference.







Florida Entomologist 88(1)


TABLE 1. RECOVERY OF CERATOGRAMMA ETIENNEI IN FLORIDA, 1998-2000.

County Year Commodity Mean % parasitism

Miami-Dade 1998 Citrus, Guava, Ornamentals 0.0
1999 Citrus 20.2
Guava 0.0
Ornamental 75.7
2000 Citrus 35.3
Ornamental 27.6
Broward 1998 Citrus, Ornamental 0.0
1999 Citrus, Ornamental 0.0
St. Lucie 1999 Citrus 0.0
Hendry 1999 Citrus 0.0
2000 Citrus 0.0


MATERIALS AND METHODS

Ceratogramma etiennei used in this study was a
Guadeloupe strain collected from D. abbreviatus
eggs by J. Etienne. The colony was reared in a lab-
oratory at 26.5 + 1C, 12:12 L:D, and approx 78%
RH, on eggs ofD. abbreviatus laid on strips of wax
paper (Etienne et al. 1990). Adult D. abbreviatus
used as a source of eggs were obtained from orna-
mentals in Homestead, Florida. Weevils were
placed in Plexiglas cages containing water, foliage
of Conocarpus erectus L., and strips of wax paper.

Host Age Preference

Laboratory test. One to 5-d-old D. abbreviatus
egg masses on strips of wax paper were placed
randomly in an experimental arena made of
translucent plastic containers (70 mm high x 70
mm long x 20 mm wide). A mated 1-d-old female
C. etiennei was introduced into each container,
provided with honey and water and host eggs of
various ages. The strips with egg masses were re-
moved after 24 h and transferred to test tubes (12
x 75 mm) separately. Tubes were plugged with
Kimwipes tissue and held 10 days for parasitoid
emergence. The number of eggs per mass used in
this experiment ranged from 50-100 and was rep-
licated 20 times. Parasitized eggs were counted
and percent parasitism was computed by dividing
the number of parasitized eggs by the total num-
ber of eggs on each wax paper strip. Weevil eggs
parasitized by C. etiennei have a golden chorion
which is characteristic of successful parasitism
(Amalin, pers. observations).

Greenhouse Test

Strips of wax paper containing 1- to 5-d-old
D. abbreviatus eggs were randomly stapled to the
upper side of leaf on 6-mo old potted C. erectus
(height ranging from 50-65 cm) placed into a ny-
lon mesh screen (91 cm wide x 91 cm long x 122
cm high) cage supported on a PVC frame. Ten 1-d-


old mated female C. etiennei were released into
the cage. The egg masses were collected after 24 h
and processed in the same way described in the
laboratory test. The test was replicated five times.
Parasitized eggs from each egg mass were
counted and the percent parasitism computed.

Effect of Female Parasitoid Age on Parasitism
One-day-old mated female parasitoids were
provided a 3-d-old weevil egg mass on wax paper
strips for 24 h in test tubes (12 x 75 mm). Egg
masses were replaced daily for 9 days (i.e., until
females were 10 d old). This experiment was repli-
cated 20 times. Exposed egg masses were collected
and processed in the previously described manner.
Parasitized eggs from each egg mass were counted
and the percent parasitism computed.

Choice Test on Selected Host Plants
Four 1-yr-old host plants, namely, lime (Citrus
aurantifolia), green buttonwood (Conocarpus
erectus), silver buttonwood (Conocarpus erectus
variety sericeus Fors. ex. DC), and pigmy palm
(Phoenix roebelenii) were tested to determine
their effects on parasitism by C. etiennei. Four
plants, one per species were placed into screen
cages (3 m x 2 m x 1 m) along with 100 adult wee-
vils (50:50 6:9). The plants were removed after
3 d, leaving twenty egg masses per host plant. All
plants were then placed in another screen cage
(1 m x 1 m x 1.22 m) and arranged in a 1 m x 1 m
square. About 1000 1-d-old C. etiennei adults
(1:0.60 9: ratio) were released within the cage
in the middle of the square. Egg masses found on
each host plant were collected three days later
and processed as above. The experiment was rep-
licated three times. Percent parasitism was com-
puted. Leaf thickness and pubescence were also
compared between the test host plants.

Effect of Plant Strata on Parasitism

Wax paper strips with two d-old weevils (n = 5
per stratum) were stapled to the upper, middle


March 2005







Amalin et al.: Influences on Parasitism by C. etiennei


and lower canopy of 6-mo-old potted C. erectus
and introduced into a nylon mesh screen cage (91
cm wide x 91 cm long x 122 cm high) supported on
PVC frames. Ten 1-d-old female and 5 male para-
sitoids were released inside the cage. Egg masses
were collected after 24 h and placed in individual
test tubes as described above. This test was repli-
cated four times. The number of parasitized eggs
was counted after 10 days.

Host Finding Behavior Video

Host finding behavior of C. etiennei was ob-
served in a Petri plate (60 x 15 mm) under a
stereoscopic microscope with attached camera
(Videoflex) and connected to a television moni-
tor (TV) (RCA) and video recorder (RCA). A
3-d-old D. abbreviatus egg mass and a 2-d-old
mated C. etiennei female were placed in a plate
for observation during daytime (1000 to 1400 h)
and nighttime (1700 to 2100 h). The set-up was
repeated five times with different individuals.
The recorded data were collected, managed, and
analyzed with the Observer Videopro 4.1 program
(Noldus Information Technology).

Statistical Analysis

Data from selected experiments were analyzed
for significant differences by the general linear
model procedure of the Statistical Analysis Sys-
tem (SAS Institute, Inc., Cary, NC). Data trans-
formations were performed on selected experi-
ments. Means were compared by Duncan's multi-
ple range test (DMRT).

RESULTS

Host Age Preference

Percent parasitism by female C. etiennei was
significantly different among host age in both lab-
oratory and greenhouse tests. Three-d-old weevil
eggs were most acceptable to the parasitoids under
laboratory and greenhouse conditions (Table 2).

Effect of Female Parasitoid Age on Parasitism

Mean egg parasitism by female C. etiennei was
affected by parasitoid age (Table 3). Percent par-
asitism significantly increased for 1- to 2-d-old
females, but decreased thereafter. Parasitism
reached a plateau when females were 3- and 4-d-
old, and declined for 5- to 9-d-old females. By the
10th day, all parasitoids were dead.

Choice of Host Plant

The highest percent parasitism of weevil eggs
by C. etiennei was found on pigmy palm followed
by green buttonwood and lime (Fig. 1). The lowest


TABLE 2. EFFECT OF AGE OF D. ABBREVIATUS EGGS ON AC-
CEPTANCE BY CERATOGRAMMA ETIENNEI UNDER
GREENHOUSE AND LABORATORY CONDITIONS.

% Mean Parasitism S.E.*
Egg age
(days) Laboratory test Greenhouse test

1 0.53 0.36 b 1.87 1.86 ab
2 0.89 0.59 ab 3.46 + 0.11 a
3 2.15 + 0.72 a 3.38 0.28 a
4 1.76 0.72 ab 2.60 1.30 ab
5 0.40 0.28 b 0.00 0.00 b

*Means with the same letter are not different according to
Duncan's multiple range test (DMRT) at P < 0.05. Data analy-
sis was performed after log transformation.


parasitism was recorded on silver buttonwood.
Variation in parasitism for different host plants is
probably influenced by the leaf thickness and pu-
bescence. For instance, leaf thickness for silver
buttonwood (0.48 0.01 mm) and green button-
wood (0.45 0.01 mm) is higher (df = 3,76; F =
81.44; P = 0.001) than lime (0.23 0.01 mm) and
pigmy palm (0.23 0.01 mm). At the same time,
pubescence is higher for silver buttonwood (3186
422 trichomes/mm2) than green buttonwood
(14.80 1.58 trichomes/mm2), lime, and pigmy
palm (0.00 0.00 trichomes/mm2).

Effect of Plant Strata on Parasitism

Higher parasitism was detected in eggs found
in the lower (85.15 3.98) and middle strata
(75.14 3.44) rather than the upper portion
(49.73 4.51) of the plant (df= 2,52; F = 4.82; P <
0.01) (Table 2). Peia et al. (unpubl.) found that
D. abbreviatus deposits more eggs on the upper
and middle plant canopy than on the lower can-
opy of silver buttonwood.


TABLE 3. PERCENT PARASITISM BY CERATOGRAMMA ETIEN-
NEI AS INFLUENCED BY AGE OF THE PARASITOID.

Age of female Mean % egg parasitism
C. etiennei (days) ( S.E.)*

1 59.35 3.71 b
2 80.04 2.90 a
3 52.87 2.79 b
4 52.46 2.50 b
5 30.03 3.58 c
6 12.13 2.50 d
7 4.74 1.63 de
8 0.76 + 1.10 e
9 0.00 0.00 e

*Means with the same letter are not different according to
Duncan's multiple range test (DMRT) at P < 0.05.







Florida Entomologist 88(1)


30

25 a

20
0.
| 15



5-
C
sb gb Im palm
Host plants

Fig. 1. Percent parasitism by Ceratogramma etiennei
on various host plants. Notes: sb = silver buttonwood, gb
= green buttonwood, Im = lime, and palm = pigmy palm.
(Note: Bars with the same letter are not different accord-
ing to Duncan's multiple range test (DMRT) at P < 0.05).


Host Finding Behavior Analysis

Video recording during the diurnal and noctur-
nal period showed that C. etiennei parasitizes its
hosts only during daytime. Parasitism activities
recorded showed three types of behavior from the
time of host detection to departure from the host.
These were probing (walking and antennation),
oviposition (drilling and egg laying), and depar-
ture (resting). The average duration in hours of a
single act of each behavior is as follows: walking
(0.15 0.10), antennation (0.08 0.01), drilling
(0.15 0.01), egg laying (0.31 0.02), and resting
(0.24 0.16). In probing, a female walked back
and forth around the host, while drumming with
its antennae. Once the egg mass was located, the
female drilled a hole through the leaf and egg
chorion to lay an egg within the weevil egg. Ovi-
position punctures were visible on parasitized
eggs. The results of the 4 h observation period are
shown in Fig. 2. Probing by the female was faster
during the first 2 h of the act, but oviposition took
longer initially. Resting time decreased in time.
These observations suggest that host finding and
acceptance (probing) was faster during first en-
counter with a fresh egg mass. Dissection of the
parasitized eggs showed that more than one egg
was deposited by C. etiennei periodically; how-
ever, only one parasitoid developed per host egg.

DISCUSSION

Results of our experiment on the host age pref-
erence showed that host age can affect choice of
the parasitoids. C. etiennei appears to prefer
younger eggs for parasitism. Similar result has
been obtained on other trichogrammatids
(Schmidt 1994). For instance, emergence rate of


3.5


1000-1100 1100-1200 1200-1300 1300-1400

Time Interval (hr)

Fig. 2. Parasitism activities by Ceratogramma etien-
nei (a 4-h observation during daytime). The vertical
scale showing time spent is in hours.


Trichogramma chilonis Ishii significantly de-
creased when eggs were older than 48 h at the
time of encounter (Guang & Oloo 1990; Schmidt
et al. 1999). The host age at the time of parasitism
appears to have implications on fitness of progeny
(Sequeira & Mackauer 1992, 1994) and parasi-
toids, which preferentially attack younger host
stages (Hagvar & Hofsvary 1986; Sequeira &
Mackauer 1988). The results obtained from the
host age preference experiment provide relevant
information regarding mass rearing ofC. etiennei.
To maximize in vivo parasitoid production, C. eti-
ennei females should be provided with D. abbre-
viatus egg no older than 3 d.
The age of the parasitoid is also crucial on suc-
cessful parasitism. A younger parasitoid is more
fecund than the older ones. The effect of age of the
parasitoid on their ability to parasitize their host
has been documented on some parasitoids (Hentz
1998; Honda 1998). For instance, the optimum
age for Cotesia marginiventris (Cresson), to suc-
cessfully parasitize larvae of Spodoptera fru-
giperda (J.E. Smith) ranges from 48 to 96 h
(Rajapakse 1992). C. marginiventris younger or
older than the above age were not able to parasit-
ize a host. Similar result has been shown in our
experiment on the effect of female parasitoid age
on parasitism, in which higher parasitism was ex-
hibited by 1- to 2-d-old C. etiennei. Knowing the
age of the parasitoids when they are most fecund
is very important in deciding what age of the par-
asitoids to release in the field to obtain a mean-
ingful level of parasitism.
Another factor that affects parasitism is the lo-
cation of the host. Insect hosts in cryptic location
provide a challenge for successful parasitism. For
instance, D. abbreviatus eggs are deposited in be-
tween two leaves. The female parasitoid has to
drill through the abaxial and adaxial surfaces of
the leaf to reach D. abbreviatus eggs; therefore,


- pobing
- oviposition
- resting


March 2005







Amalin et al.: Influences on Parasitism by C. etiennei


successful oviposition may be facilitated when
weevil eggs are deposited on leaves with thinner
blades and non-pubescent foliage, such as pigmy
palm. These leaf features might explain why
D. abbreviatus eggs on silver buttonwood were the
least parasitized among the four host plants. Vari-
ation in parasitism on various plants was also ob-
served by Peter (1990). He found that maximum
parasitism byApanteles taragamae Viereck on Di-
aphania indica (Saunders) was recorded on two
varieties of cucurbits with smoother leaves. Phys-
iological factors (i.e., leaf odor) cannot be ruled out.
Ceratogramma etiennei search, find, and at-
tack their host in cryptic locations, however, the
cues they use to find D. abbreviatus eggs are still
unclear. Short range and contact chemical cues
associated with physical cues arising from the
host plants or from the host are reported to affect
host recognition and acceptance by some parasi-
toids. This might also be true for C. etiennei. Pre-
liminary tests showed that chemical and physical
cues play an important role in host recognition by
C. etiennei (D. Amalin et al. unpublished data).
The chemical cues can be found on scales from the
weevil elytra, usually left behind near the egg
mass by the female during oviposition, on adult
feces, or on the substance produced by the female
to cement the eggs between leaves. Further stud-
ies to identify the factors involving host recogni-
tion and host acceptance by C. etiennei are worth
investigating.

ACKNOWLEDGMENTS

We thank M. Codallo, N. Nurhassanah, J. Alegria,
and Z. Alegria for the technical assistance and J. Eti-
enne (INRA) for providing C. etiennei. We are grateful to
Nancy Epsky and Tom Weissling for letting us use their
VideoPro software to complete the behavior part of the
manuscript. We also thank J. D. Pinto for confirmation
of parasitoids identification. We thank H. Frank and J.
Capinera for helpful suggestions to improve this manu-
script. This research was supported by T-STAR and
FCPRAC grants to Jorge E. Peia. Florida Agricultural
Experiment Station Journal Series R-09985.

REFERENCES CITED

ADAIR, R. C., H. N. NIGG, S. E. SIMPSON, AND L. LEFEVRE.
1998. Ovipositional preferences of Diaprepes abbre-
viatus (Coleoptera: Curculionidae). Florida Entomol.
81: 225-234.
BEAVERS, J. B., S. A. LOVESTRAND, AND A. G. SELHIME.
1980. Establishment of the exotic parasite Tetrasti-
chus haitiensis (Hym: Eulophidae) and recovery of a
new Trichogramma (Hym: Trichogrammatidae)
from root weevil egg masses in Florida. Entomoph-
aga 25: 91-94.
BEAVERS, J. B., C. W. McCOY, AND D. T. KAPLAN. 1983.
Natural enemies of subterranean Diaprepes abbre-
viatus (Coleoptera: Curculionidae) larvae in Florida.
Environ. Entomol. 12: 840-843.
ETIENNE, J., H. MAULEON, AND B. PINTUREAU. 1990. Bi-
ologie et dynamiques de Ceratogramma etiennei


(Hymenoptera: Trichogrammatidae) parasite de Di-
aprepes abbreviatus (L.) (Coleoptera: Curculionidae)
en Guadeloupe. Les Colloques del INRA 58: 459-468.
FIGUEROA, W., AND J. ROMAN. 1990. Parasitism of ento-
mophilic nematodes on the sugarcane rootstalk
borer, Diaprepes abbreviatus (L.) (Coleoptera: Cur-
culionidae) larvae. J. Agric. University of Puerto
Rico 74: 197-202.
GUANG, L. Q., AND G. W. OLOO. 1990. Host preference
studies on Trichogramma sp. nr. Mwanzai Schulten
& Feijen (Hymenoptera: Trichogrammatidae) in
Kenya. Insect Sci. Appl. 11: 757-763.
HAGVAR, E. B., AND T. HOFSVANG. 1986. Parasitism by
Ephedrus cerasicola (Hymenoptera: Aphidiidae).
Entomophaga 31: 337-346.
HALL, D., J. PENA, R. FRANQUI, R. NGUYEN, P. STANSLY,
C. McCOY, S. LAPOINTE, R. ADAIR, AND R. BULLOCK.
2001. Status of biological control by egg parasitoids of
Diaprepes abbreviatus (Coleoptera: Curculionidae) in
citrus in Florida and Puerto Rico. BioControl 46: 61-70.
HENTZ, M. G. 1998. Development, longevity, and fecun-
dity of Chelonus sp. nr. curvimaculatus (Hymenop-
tera: Braconidae), an egg-larval parasitoid of pink
bollworm (Lepidoptera: Gelechiidae). Environ. Ento-
mol. 27: 443-449.
HONDA, T. 1998. Age-related fecundity and learning
ability of the egg-larval parasitoid Ascogaster reticu-
latus Watanabe (Hymenoptera: Braconidae). Biol.
Control 13: 177-181
PENA, J. E., J. ETIENNE, R. DUNCAN, AND J. PINTO. 1998.
Introduction of Ceratogramma etiennei (Hy-
menoptera: Trichogrammatidae) for biological control
ofDiaprepes abbreviatus in Florida, USA, pp. 145-148
In S. Hassan [ed.], Egg Parasitoids, 5th International
Symposium, IIBC, Cali, Colombia, 356. Berlin.
PENA, J. E., AND D. M. AMALIN. 2000. Biological control
of Diaprepes abbreviatus by parasitoids, pp. 66-76 In
S. H. Futch [ed.], Diaprepes Short Course. Coopera-
tive Extension Service Florida Agricultural Experi-
ment Station. Citrus Research & Education Center,
Lake Alfred, FL. March 22, 2000.
PETER, C. 1990. Influence of host plants on the parasit-
ism ofDiaphania indica (Lepidoptera: Pyralidae) by
Apanteles taragamae (Hymenoptera: Braconidae).
Insect Sci. Appl. 11: 903-906.
RAJAPAKSE, R. H. S. 1992. Effect of host age, parasitoid
age, and temperature on interspecific competition
between Chelonus insularis Cresso, Cotesia margin-
iventris Cresson and Microplitis manilae Ashmead.
Insect Sci. Appl. 13: 87-94.
RICHMAN, D., W. WHITCOMB, AND W. BUREN. 1983. Pre-
dation on neonate larvae of Diaprepes abbreviatus
(Coleoptera: Curculionidae) in Florida and Puerto
Rico citrus groves. Florida Entomol. 66: 215-222.
SCHMIDT, J. M. 1994. Host recognition and acceptance
by Trichogramma, pp. 166-200 In E. Wajnberg and
S. A. Hassan [eds.], Biological Control with Egg Par-
asitoids. Guild Ford, UK.
SCHMIDT, M., G. MADEL, AND R. SCHMUCK. 1999. Im-
pact of Vairimorpha sp. (Microsporidia: Burnellidae)
on Trichogramma chilonis (Hymenoptera: Tricho-
grammitidae), a hymenopteran parasitoid of the
cabbage moth, Plutella xylostella (Lepidoptera:
Yponomeutiade). J. Invertebr. Pathol. 74: 120-126.
SEQUEIRA, R., AND M. MACKAUER. 1992. Covariance of
adult size and development time in the parasitoid
wasp Aphidius ervi in relation to the size of host,
Acrytosiphon pisum. Evol. Ecol. 6: 34-44.







82 Florida Entc



SEQUEIRA, R., AND M. MACKAUER. 1994. Variation in se-
lected life history parameters of the parasitoid wasp.
Aphidius ervi: influence of host developmental
stage. Entomol. Exp. Appl. 71: 15-22.
SEQUEIRA, R., AND M. MACKAUER. 1988. Effects of para-
sitism by Praon pequdorum on age specific fecundity
and population growth of the pea aphid, Acyrthosi-
phon pisum. Entomol. Exp. Appl. 48: 179-185.
SIMPSON, S., H. NIGG, N. COILE, AND R. ADAIR 1996. Di-
aprepes abbreviatus (Coleoptera: Curculionidae) lar-
vae. Florida Entomol. 65: 150-158.


Im


ologist 88(1) March 2005



SIRJUSINGH, C., A. KERMARREC, H. MAULEON, C. PAVIS,
AND J. ETIENNE. 1992. Biological control of weevils
and white grubs on bananas and sugarcane in the
Caribbean. Florida Entomol. 75: 548-562.
WHITCOMB, W. H., T. GOWAN, W. BUREN. 1982. Preda-
tors of Diaprepes abbreviatus (Coleoptera: Curcu-
lionidae) larvae. Florida Entomol. 65: 150-158.
WOODRUFF, R.E. 1964. A Puerto Rican weevil new to
the United States (Coleoptera: Curculionidae). Fla.
Dept. Agric. Div. Plant Industry. Entomol. Circ. 30:
1-2.







Puche et al.: Effect of Elevation and Host on C. capitata


EFFECT OF ELEVATION AND HOST AVAILABILITY ON DISTRIBUTION
OF STERILE AND WILD MEDITERRANEAN FRUIT FLIES
(DIPTERA: TEPHRITIDAE)

HELENA PUCHE1, DAVID G. MIDGARDEN2, OSCAR OVALLE3, PAUL E. KENDRA1,
NANCY D. EPSKY*', PEDRO RENDON3 AND ROBERT R. HEATH'
'Subtropical Horticulture Research Station, Agricultural Research Service
United States Department of Agriculture, 13601 Old Cutler Rd., Miami, FL 33158

2Duty station: USDA/APHIS-International Services, United States Embassy, Guatemala, APO AA 34024-3319

3USDA/APHIS-PPQ, United States Embassy, Guatemala, APO AA 34024-3319

*To whom reprint requests should be addressed

ABSTRACT

Effects of elevation and host fruit availability on the distribution of the Mediterranean fruit
fly, Ceratitis capitata (Wiedemann), were evaluated with cylindrical traps baited with a fe-
male-biased food-based synthetic lure. Tests were conducted in the Santa Maria valley, Gua-
temala during a sterile male release program. Traps were placed in or near host trees
(primarily coffee and citrus) and in non-host trees when no hosts were available. Trap loca-
tions were grouped according to elevation every 170 m. Elevation group midpoints were
1103, 1273, 1443, and 1613 m above sea level. The spatial distributions of sterile males, wild
males, and females were clumped throughout the 13 wk of sampling. More wild female flies
were captured in coffee in the 1273 m elevation and on non-host trees in the 1103 m eleva-
tion. The number of wild males was directly related to the number of wild females captured,
and the sex ratio (female: male) was highest at the 1443 and 1613 m elevation ranges. There
was no relationship between the number of sterile males and number of wild females in the
traps at any elevation. At all elevation ranges, an inverse relationship was observed between
the numbers of wild females and males with the mean numbers of sterile males per trap.
Wild C. capitata populations appeared to decrease when 40 sterile males were captured per
trap with wild females per week. The results indicated that, during the sampling period
evaluated, coffee appeared to be the main host plant for the wild population, C. capitata were
more abundant at the 1273 m elevation range than at other elevations. Additional or alter-
native host species may harbor the female population at other times.

Key Words: Ceratitis capitata, fruit fly host plant, elevation, sterile insect technique, fruit fly
spatial distribution.

RESUME

Plantas hospederas y elevaci6n preferencial por la mosca Mediterranea de la fruta, Ceratitis
capitata (Wiedemann), fueron evaluadas con trampas cilindricas con cebo sint6tico que atrae
hembras. Experimentos fueron realizados en Guatemala durante el program de liberaci6n
de machos est6riles. Trampas fueron colocadas en o cerca de arboles hospederos (principal-
mente caf6 y citricos) y en otros arboles no hospederos). Las trampas fueron agrupadas de ac-
uerdo a su elevaci6n cada 170 m, en los rangos de elevaci6n 1103, 1273, 1443, y 1613 m por
encima del nivel del mar. La distribuci6n espacial de los machos est6riles, hembras y machos
f6rtiles y salvajes fue agrupada a trav6s de las 13 semanas de muestreo. Las hembras salvajes
fueron capturadas s61o en caf6 (mas en el rango de elevaci6n 1273) y en las plants no identi-
ficadas (mas en el rango de elevaci6n 1103). El numero de machos salvajes fue proporcional
al de hembras salvajes y el radio sexual (hembra: macho) fue mayor en los rangos de elevaci6n
1443 y 1613. El numero de machos est6riles no fue afectado por el incremento de hembras sal-
vajes en las trampas. En todos los rangos de elevaci6n, se encontr6 una relaci6n inversa entire
el numero promedio de hembras y machos salvajes con el numero promedio de machos es-
t6riles. La poblaci6n salvaje de la mosca del mediterraneo decreci6 cuando los machos es-
t6riles llegaron a ser 40 por trampa con hembras salvajes por semana. Los resultados
indicaron que el caf6 pareci6 ser la plant hospedera principal de la poblaci6n salvaje durante
el period de muestreo, y que durante este, las moscas del Mediterraneo fueron mas abundan-
tes en el rango de elevaci6n de 1273 m que en otros rangos de elevaci6n. Otras plants hos-
pederas alternatives podrian acarrear a la poblaci6n de hembras salvajes en otros moments.

Translation provided by the authors.







Florida Entomologist 88(1)


Ceratitis capitata (Wiedemann), the Mediter-
ranean fruit fly, is considered the most destruc-
tive agricultural pest in the world. Even though it
is not established in the continental U.S., its po-
tential impact on the California and stone fruit in-
dustry has been projected to be about $0.5-1
million in agricultural losses per year (Siebert &
Pradhan 1990). It has been reported to attack
more than 260 species of fruits and vegetables
world-wide (Liquido et al. 1991; Ovruski et al.
2003). Adult females damage fruit by depositing
their eggs in holes made under the skin of the
fruit. Availability of host plants suitable for ovipo-
sition is a key factor for understanding the popu-
lation dynamics of the fruit fly and its distribution
over space and time. This information can be used
for planning management strategies for this pest.
If the plants are not in fruit or have only low qual-
ity fruit, mature females either arrive in low num-
bers or emigrate rapidly and fly considerable
distances before finding host plants with accept-
able fruits (Prokopy & Roitberg 1989). Therefore,
availability of host plants is considered a key fac-
tor in the temporal pattern of fruit fly abundance
(Bess et al. 1963; Newel & Haramoto 1968; Mala-
vasi & Morgante 1981; Vargas et al. 1983).
Successful eradication of the Mediterranean
fruit fly has been obtained by the sterile insect
technique (SIT) in combination with bait sprays
in Mexico, and in the U.S. in California and Flor-
ida (Vargas 1989). Endemic populations of C. cap-
itata occur in Guatemala, where efforts to
suppress fruit fly populations in large portions of
the country are occurring through the Programa
Moscamed, a trilateral effort of the governments
of the U.S., Mexico, and Guatemala (Linares &
Valenzuela 1993). The primary effort in Guate-
mala is to maintain a barrier to prevent move-
ment of C. capitata into Mexico and the U.S. The
areas under SIT activity include a fly free area
(57% of area, located in the northwest, closest to
the border with Mexico), an infested area (33.8%
of area, located in the southeast, where high pop-
ulations of C. capitata are present) and a control
area (9.2% of area, located between the free area
and the infested area) (Linares & Valenzuela
1993). Traps are placed throughout this area and
are monitored by Moscamed, and trapping data
indicate that up to 98% of the region is under suc-
cessful control, with no wild flies captured. How-
ever, localized isolated populations or "hot spots"
of wild flies still persist in the infested area, and
identification of the factors responsible for the hot
spots is critical to the success of the eradication
effort. The Santa Maria area of Guatemala is lo-
cated close to the southeast edge of the infested
area, and contains isolated populations of C. cap-
itata. A study was initiated to evaluate the spatial
distribution of endemic wild and released sterile
C. capitata in this area and to identify effects due
to elevation and host plant availability.


MATERIALS AND METHODS

Traps and Lures

Cylindrical open-bottom dry traps (OBD;
Heath et al. 1996) were baited with a three com-
ponent lure consisting of ammonium acetate, pu-
trescine, and trimethylamine, formulated as
three separate patches backed with adhesive for
securing inside the trap (Suterra, Inc., Bend, OR).
The OBD trap (9 cm diam by 15 cm tall) is made
from opaque green waxed cardboard and has
three holes (2 cm diam) evenly spaced around the
midline of the trap body. A yellow sticky insert
(7.6 by 12.7 cm; Suterra LLC, Bend, OR) was
hung inside the center of the trap to retain flies.
Sticky inserts were replaced weekly, the three
component synthetic lures were replaced every 4
wk, and traps were replaced when the cardboard
deteriorated.

Fly Release

The sterile male-only tsl strain of C. capitata
(Vienna-7) used in this study was produced by
gamma irradiating pupae with 10Krad (100 gray)
at the Moscamed rearing facility, Guatemala. Ir-
radiated pupae were treated with 4g/liter of pu-
pae with powdered florescent dye (Dayglo Color
Corporation, Cleveland, OH) to mark the adults
on emergence. C. capitata adults were kept at
23C and fed a mixture of 15% sugar and 84.99%
water thickened by 0.01% agar. At three to four
days of age, flies were chilled to near 0C, loaded
into chilled-fly release machines (K&K Aircraft,
Bridgewater, VA) installed in a Cessna Caravan,
and released at an average rate of 3,600 flies per
ha over the test area from an altitude of 2500 to
3000 m above sea level.

Protocol for Field Trial

The study was conducted in a geographically
diverse area of Guatemala under SIT activity. The
field site was approximately 20 km2 and was cen-
tered at longitude -91.53 and latitude 14.71 in
the Santa Maria valley between the Santa Maria
and Santo Tomas volcanoes in the province of
Quetzaltenango. Fifty-one traps were deployed
throughout the valley at different elevations and
host plants to monitor the presence of the wild
populations and the sterile males released in the
area. Trap sites were determined by generating a
grid of potential trap locations based on a point in
the center of the valley and spaced evenly 500 m
apart. Traps were then placed as close to these po-
tential trap locations as possible with GPS
(Garmin International, Inc., Olathe, KS, GPS III
Plus). A potential trap location was one that had
road access, where the terrain (rivers, mountain,
etc.) did not interfere with trap deployment, with


March 2005







Puche et al.: Effect of Elevation and Host on C. capitata


a known history of detection of C. capitata or
where attack was likely due to phenology of
known hosts or presence of wild alternative hosts.
Potential trap locations were eliminated if they
were inaccessible to the trappers, if they were
bare of trees or structures to support a trap, or if
permission for access was not granted. Traps
were placed primarily in or near host trees, in-
cluding coffee (Coffea arabica L.), or trees within
a coffee grove, sweet orange (Citrus sinensis Os-
beck), nispero (Manilakara zapata [L.] P. Royen),
guava (Psidium guajava L.), mango (Mangifera
indica L.), apple (Malus pumila P. Mill), melon
(Cucurbita melo L.), and loquat (Eriobatyra
japonica Lindl.). If no host trees were near the
prospective location, a trap was placed in a non-
host tree. Elevation of the traps varied from ap-
proximately 1,000-1,700 meters above sea level,
and this range was divided into four equal groups
of 170 m to determine elevation groups. Eleva-
tions (elevation ranges) were designated by their
midpoint, and considered as 1103 m (1017-1187),
1273 m (1187.1-1357), 1443 m (1357.1-1527), and
1613 m (1527.1-1697).
The traps were sampled weekly for 13 wk from
June to October 2002 (recorded as wk 26-38 out of
52 wk per year). During this time only a few hosts
such as guava, citrus, and coffee were fruiting and
available for C. capitata colonization. All flies cap-
tured were taken to the Moscamed laboratory in
Mazatenango, Guatemala, examined to deter-
mine sex and sterility status following standard
protocols (Anonymous 1983), and number of ster-
ile males, wild males, and females were recorded.
Meteorological data was not available.

Host Fruit Availability

Information on host fruit availability in the
Santa Maria valley was obtained from records
maintained by Moscamed. As part of the Mos-
camed protocol, fruit sampling is carried out in an
extensive way to complement trapping (Linares &
Valenzuela 1993), and host fruits are obtained
from all places including urban, rural, wild, agri-
cultural, and cultivated areas. Sampling routes
are determined according to location of fruit trees
inside private properties, access areas, and roads.
Fruits were collected directly from trees when
they were mature but still with solid (or firm) con-
sistency. Sampling numbers varied according to
fruit: 30-60 coffee or cherries, and 4-6 for other
fruit trees. If pest levels are low, only fruits sus-
ceptible to the C. capitata attack with circular yel-
low or necrotic spots are collected. If many trees
are present, samples are taken from different
trees as long as they are not separated by more
than 100 m. If fruits are scarce, they are collected
from known hosts or from those that had higher
probability of infestation, i.e., from the sunny side
of the host plant at different heights. Historical


data on collection dates and number of mature
fruit sampled per collection date were used to es-
timate pattern of host fruit availability in trees
used for trap placement in this study. Infestation
levels were not recorded.

Data Analysis

Data were checked for homocedasticity prior to
statistical analysis. To normalize the data and sta-
bilize the variance, numbers of fruit flies captured
per trap per week were square root-transformed (x
+ 0.5) and a repeated measure ANOVA was used
to detect effects of sampling date and elevation
range on female-male ratio. To detect differences
in trap captures among different hosts and eleva-
tions, and to compare female:male ratio among el-
evation ranges, a Kruskal-Wallis ANOVA was
used followed by a non-parametric multiple com-
parison procedure (Siegel & Castellan 1988) when
no transformation normalized the data (SAS In-
stitute 1998). The variance to mean ratio of the
numbers of fruit flies captured each week sam-
pled, for each fruit fly type (wild female, wild male,
and sterile male) was used to determine the fruit
fly spatial distribution (Southwood 1978).

RESULTS AND DISCUSSION

Number of traps was variable at each eleva-
tion range and host plant. Traps were deployed on
25 non-host species, 24 coffee trees, one loquat
and one orange tree (Citrus spp.). On coffee, 4, 14,
3, and 3 traps were deployed at the 1103, 1273,
1443, and 1613 m elevation ranges, respectively.
On non-host species, 2, 4, 10, and 6 traps were de-
ployed at the 1103, 1273, 1443, and 1613 m eleva-
tion ranges, respectively. In the 13 wks of
sampling, wild females were captured in 5, 68, 6,
and 9 traps on coffee and in 3, 1, 6, and 3 traps on
non-host species at the 1103, 1273, 1443, and
1613 m elevation ranges, respectively. Five traps
also were deployed above 1697 m, but no wild or
sterile flies were ever captured in those traps.
Therefore, these five traps were not considered in
the analyses.
Because the wild females are the target for
control and zero values confounded the results
(no statistical differences were detected among el-
evations, plant species or between wild females or
males, and sterile males), only traps that cap-
tured wild females were used in the analyses. The
only traps that captured wild females were those
traps deployed on coffee and non-host species. Ta-
ble 1 shows the number of traps for each sampling
date and for the 13 wks of sampling, and the av-
erage number of wild females, wild males, and
sterile males captured at different elevations and
host plants. The highest percentage of traps with
wild females was found on coffee at the 1273 m el-
evation range, representing 41% of the traps that







Florida Entomologist 88(1)


TABLE 1. PERCENT OF SAMPLES WITH WILD FEMALES (OUT OF TOTAL NUMBER OF TRAPS TIMES NUMBER OF SAMPLES
(13 WEEKS)) IN EACH ELEVATION GROUP AND IN EACH HOST GROUP, AND NUMBER OF C. CAPITATA CAPTURED
IN TRAPS PLACED IN COFFEE. TESTS WERE CONDUCTED FROM JUNE TO OCTOBER 2002, IN SANTA MARIA,
GUATEMALA.

Average (+SE) number of flies per trap per week
Elevation Non-host
range (m) Coffee n species n Wild females Wild males Sterile males

1103 10.4% (52) 4 12.5% (26) 2 1.0 0.0 b 0.5 0.2 b 10.8 4.8 a
1273 40.5% (182) 14 2.1% (52) 4 5.4 1.1 a 3.8 0.9 a 26.1 3.3 a
1443 16.7% (39) 3 5.0% (130) 10 3.0 0.7 ab 0.6 0.3 ab 16.2 3.8 a
1613 25.0% (39) 3 4.2% (78) 6 1.9 0.6 ab 0.5 0.2 b 10.8 1.9 a

Means in the same column followed by the same letters are not different (Kruskal-Wallis ANOVA, P < 0.05); n represents the
total number of traps deployed on each host at each elevation range.


captured females. Captures of wild females at
this elevation range were not significantly differ-
ent than those captures at the 1443 and 1613 m
elevation ranges but were higher than those at
the 1103 m elevation range. Similar results were
obtained for the wild males. The mean number of
sterile males in traps with wild females on coffee
was not significantly different among elevation
ranges (Table 1). On the non-host trees, the high-
est percentage of traps with wild females was
found at the 1103 m elevation range but this ef-
fect of elevation was not significant (Table 1, H =
0.241; df = 3, P = 0.9708). Findings of sterile
males in comparable numbers at all elevation
ranges may indicate that the sterile release pro-
gram was successful in distributing the flies ade-
quately to pursue an effective control of the wild
female populations.
The peak of maturation for all the host plants
available for C. capitata colonization was in mid
May, and maturation rapidly decreased by the
end of the summer. During late June, when this
experiment began, host plants such as caimito
(Chrysophyllum cainito L. (syn. Achras caimito
Ruiz & Pavon)), mango, and mandarin (Citrus re-
ticulata L.) only had a few mature fruits left on
the trees. Coffee, sweet orange, sour orange (Cit-
rus aurantium L.), and guava trees had the high-
est numbers of ripe fruits among the host plants
evaluated at the end of June and throughout the
experiment. Only guava, citrus (Citrus spp.), and
coffee were fruiting and available for C. capitata
colonization during the sampling period. No in-
formation was collected on the phenology of the
trees where the traps were deployed. Therefore,
we cannot infer the relation between host avail-
ability and trap captures.
The spatial distributions of sterile males, wild
males, and wild females were clumped through-
out the sampling period as indicated by the vari-
ance to mean ratio (Table 2), except on wk 38
when the sterile males appeared to be distributed
at random. However, the overall spatial distribu-
tion of the sterile males was clumped. Previous


studies also found a patchy distribution of the
Mediterranean fruit fly under low population
densities (Bateman 1972; Vargas et al. 1983;
Nishida et al. 1985; Harris & Lee 1986, 1987;
Harris et al. 1993; Papadopoulos et al. 1996;
Prokopy et al. 1996; Israely et al. 1997; Katsoyan-
nos et al. 1998; Papadopoulos et al. 2001).
Figure 1 presents the population dynamics of
the wild females at the four elevation ranges on
coffee and on the non-host trees. Even though the
wild females appeared on both host and non-host
trees at the beginning of the study (wk 26-30),
they disappeared from the non-host trees after
wk 32 and increased on coffee at all elevations.
This observation might be an indication that
while coffee and non-host trees are flowering or
ripening, C. capitata populations use both tree
species, but when ripening of coffee occurs on wk
33 and no other fruits or flower plants are avail-
able at this time, the female flies move to the


TABLE 2. MEAN/VARIANCE RATIO TO DETERMINE THE SPA-
TIAL DISTRIBUTION OF CERATITIS CAPITATA CAP-
TURED IN CYLINDRICAL TRAPS BAITED WITH A
FOOD-BASED SYNTHETIC ATTRACTANT IN SANTA
MARIA, GUATEMALA.

Week Wild females Wild Males Sterile males

26 0.02 0.03 0.04
27 0.09 0.00 0.02
28 0.10 0.37 0.21
29 0.42 0.61 0.01
30 0.24 0.29 0.01
31 0.46 0.80 0.02
32 0.11 0.12 0.03
33 0.06 0.09 0.03
34 0.10 0.08 0.03
35 0.31 0.16 0.15
36 0.61 0.49 0.81
37 0.22 0.50 0.52
38 0.45 0.57 1.04
Total 0.05 0.06 0.02


March 2005







Puche et al.: Effect of Elevation and Host on C. capitata


2.0
NON-HOST
1.5 -oo COFFEE


01





LL
ci)
U-


1103


1.0 oy A ,

0.5 A 0
gO 0

0.0 TUk

20
0 1273
15 :

10

5 A
lO '.

10

8 o0'3% 1443

6 I

4 0
2 oo *
2 1
n


\ 1613
00
0
*
* 0
* 0


24 26 28 30 32 34 36 38 40


WEEK


Fig. 1. Population dynamics of wild female C. capi-
tata captured in cylindrical traps baited with food-based
synthetic attractant during 12 weeks of sampling at dif-
ferent elevation ranges on coffee (dotted line) and non-
host trees (solid line) in Santa Maria, Guatemala.


coffee areas in search of better feeding and ovipo-
sition sites. This observation agrees with Papa-
dopoulos et al. (2003) findings that the
Mediterranean fruit fly females aggregate in
space in response to the changing phenology of
host trees and to the sequential availability of
ripe or semi-ripe fruits in an orchard. Moreover,
C. capitata are known to adjust their foraging


behavior in response to the changes in the spatial,
temporal, and seasonal distribution of food and
other resources (Hendrichs et al. 1991).
Because captures in traps on non-host trees
were less than two females per trap per week for
most of the study, only data from traps in coffee
were used in the remaining analyses. A direct re-
lationship between the mean number of wild fe-
males and males was found at different elevation
ranges on coffee (Fig. 2). The number of wild
males was directly proportional to the number of
wild females, but the female:male ratio varied
among elevation ranges (F = 22.809; df = 1, 47; P
< 0.001). The highest female:male ratios were 4.0


Sou

60

S40

QG
-2o-

20

0)


0 2 4 6 8 10 12 14 16 18 20

B




4


0 2 4 6 8 10 12 14 16 18 20


0 2 4 6 8 10 12 14 16 18 20


Wild Females I trap / week

Fig. 2. Relationship between (A) mean number of
wild female and male C. capitata and (B) mean number
of wild female and sterile male C. capitata captured in
cylindrical traps baited with food-based synthetic at-
tractant and placed in coffee trees at different elevation
ranges (*:1103 m, +:1273 m, A:1443 m, *:1613 m above
sea level) in Santa Maria, Guatemala. Lines indicate
regression lines for 1103 m (- -), 1273 m (-), 1443 m
(- -), and 1613 m (...). For wild-males/trap/week vs
wild females/trap/week: y = 0 + 0.43x (r2= 0.26, for 1103
m); y = -0.19 + 0.71x (r2 = 0.89 for 1273 m); y = -0.17 +
0.26x (r2 = 0.47, for 1443); y = 0.04 + 0.25x (r2 = 0.63, for
1613 m). For sterile males/trap/week vs wild females/
trap/week y = 11.14 + 0.36x (r2 = 0.37, for 1103 m); y =
20.50 + 0.56x (r2 = 0.02, for 1273 m); y = 5.08 + 0.50x (r2
= 0.02, for 1443 m) and y = 4.03 + 1.10x (r2 = 0.10, for
1613 m).







Florida Entomologist 88(1)


+ 2.
1613
was
capt
ture
(AN
ever
male
inve
num
trap
ditio
succ
tions
with
duct
male
rele;
over
for
Barr
over
ture
fly c
male
the
bers
trap
male
tio b
fema
per
cati(
steri
was
adju
Elev
teph
troce
low
whe
Daci


30

225

20

0) 15

E 10


F
traps
tata


0 and 2.3 0.6 (mean SE) at the 1443 and dian Ocean cucurbit fly, Dacus (Dacus) demerezi
Sm elevations, respectively. No relationship (Bezzi) that occupies high altitude areas (Etienne
detected between the number of wild females 1972; Vayssieres & Carel 1999).
ured and the number of sterile males cap- After wk 32, numbers of sterile males de-
d when all the elevations were considered creased in all traps and the numbers of females
OVA, F = 1.763; df = 1, 47; P = 0.1671). How- began to increase at all elevation ranges. On wk
after separating the sterile male and wild fe- 34, a decrease of the sterile males in the traps was
e captures by elevation range (Fig. 3.) an observed, and an increase of the wild females oc-
rse relationship was observed between the curred by wk 37. The inverse relationship of the
ibers of wild females and sterile males per sterile males and the wild populations of C. capi-
at the 1273 m elevation range. This is an ad- tata is an indication that the aerial releases of
'nal indication that the sterile releases were sterile C. capitata were successful in reducing the
essful in controlling the wild female popula- wild populations in Santa Maria, Guatemala.
s. When the sterile males reached 40 per trap This result reiterates previous eradication efforts
-wild-females per week, a corresponding re- of this pest at the Mexico-Guatemala border,
ion was observed in the wild population of fe- which prevented the northward spread of the fly
es (Fig. 3). A successful SIT program requires into Mexican territory (Orozco et al. 1994).
easing enough sterile flies so that at least an Data from this study support the hypothesis
flooding ratio of 100 sterile males is reached that elevation and host fruit availability affect
each wild fly captured (Garcia et al. 1999; the distribution of wild flies in the habitat of this
ry et al. 2003). This evaluation is averaged valley. Wild male and female fruit flies were more
all traps, also including those that do not cap- abundant at the 1273 m elevation range on coffee
any wild females. Furthermore, it is based on throughout the sampling period. Even though
captures on Jackson traps that target only higher mating success of sterile males was re-
e flies. In this study, OBD traps were used for ported at low elevation sites (700 m) in Guate-
analyses. Therefore, the discrepancy in num- mala (Shelly et al. 2003), it is important to direct
(40 versus 100) may be due to the exclusion of C. capitata control efforts with SIT to those areas
s with zero-wild-females, and to the use of fe- where the wild populations persist as "hot spots"
e biased traps resulting in an overflooding ra- at higher elevations. Micro-environmental differ-
>elow the required average. Because the wild ences in humidity and temperature, as well as
ale populations decreased at 40 sterile males host fruit maturity, may have contributed to cre-
traps-with-wild-females, this may be an indi- ating the favorable conditions for wild fruit flies.
on that the required overflooding ratio of 100 Microclimatic environmental parameters that
le males per wild female per trap captured regulate clumped distribution of the wild fruit
reached. Additional studies are required to flies remain to be identified.
st the over-flooding ratio based on OBD traps. Because the number of samples was unbal-
'ation effects have been observed with other anced among elevation ranges, a balanced sam-
ritid species. For example, the melon fly, Bac- pling scheme on coffee and other host plants
?ra cucurbitae (Coquillet), is found mostly at among elevation ranges is needed to identify
and medium altitudes in Reunion Island other possible host plant preferences by C. capi-
re it competes with the Ethiopian cucurbit fly, tata wild populations. Furthermore, detailed in-
us ciliatus Loew, both competing with the In- formation of fruiting phenology needs to be
recorded to determine which host plants play a
key role in the C. capitata population increases
60 (Ovruski et al. 2003). We hypothesize that differ-
ent available hosts harbor populations of differ-
50 ent sexes, as reported by Papadopoulos et al.
.-4. 40 (2003), and also that different micro-environmen-
tal conditions (Eskafi & Kolbe 1990) may favor
*0 the survivorship of different fruit fly sexes. Be-
'20 cause several factors may be interacting and af-
Sfecting the spatial distribution of C. capitata in
10 E this area, micro-environmental conditions and
0 fruit availability at different elevation ranges are
needed to test these hypotheses that may explain
--10 the variation in sex ratios at different elevation
24 26 28 30 32 34 36 38 40 ranges. Although coffee appeared to be the main
WEEK host plant for the wild population during the sam-
ig. 3. Mean number of sterile males per week in pling period reported herein, additional or alter-
s with wild females (...), and sterile male C. capi- native host species may harbor the female
(-) per week at the 1273 m elevation range. population at other times.


March 2005







Puche et al.: Effect of Elevation and Host on C. capitata


ACKNOWLEDGMENTS

The authors thank Gordon Tween (USDA/APHIS-
IS) and Juan Jose Mel6ndez (Moscamed) for their kind
cooperation and support for this study. We also thank
the trappers Luis Aquino and Myron Niedes, and other
personnel from Moscamed for determination of fruit fly
sex and sterility and Don Tomas and Nikos Papadopou-
los for reviewing this manuscript. This article reports
the results of research only. Mention of a proprietary
product does not constitute an endorsement or recom-
mendation by the USDA for its use.

REFERENCES CITED

ANONYMOUS. 1983. Manual for the differentiation of
wild (fertile) Mediterranean fruit flies, Ceratitis cap-
itata (Wied.), from irradiated (sterile) ones. Pro-
grama Mosca Del Mediterraneo Talleres Graficos de
la Naci6n, M6xico, D.F., M6xico.
BARRY, J. D., T. E. SHELLY, D. O. MCINNIS, AND J. G.
MORSE. 2003. Potential for reducing overflooding ra-
tios of sterile Mediterranean fruit flies (Diptera: Te-
phritidae) with the use of ginger root oil. Florida
Entomol. 86: 29-33.
BATEMAN, M. A. 1972. The ecology of fruit flies. Annu.
Rev. Entomol. 17: 493-518.
BESS, H. A., F. H. HARAMOTO, AND A. D. HINCKLEY.
1963. Population studies of the oriental fruit fly, Da-
cus dorsalis Hendel (Diptera: Tephritidae). Ecology
44: 197-201.
ESKAFI, F. M., AND M. E. KOLBE. 1990. Infestation pat-
terns of commonly cultivated, edible fruit species by
Ceratits capitata and Anastrepha spp. (Diptera: Te-
phritidae) in Guatemala and their relationship to en-
vironmental factors. Environ. Entomol. 19: 1371-1380.
ETIENNE, J. 1972. Les principles Tephritids nuisibles de
lile de La Reunion. Ann. Soc. Entomol. France 8:
485-491.
GARCIA, E., P. RENDON, D. MCINNIS, AND
R. CASTANEDA. 1999. Evaluation of competitiveness
between two strains of Mediterranean fruit fly Cer-
atitis capitata (Wied.) Villa Canales, Guatemala, pp
39, Working group on fruit flies of the western hemi-
sphere, Guatemala City, Guatemala.
HARRIS, E. J., AND C. Y. L. LEE. 1986. Seasonal and an-
nual occurrence of Mediterranean fruit flies
(Diptera: Tephritidae) in Makaha and Waianae val-
leys, Oahu, Hawaii. Environ. Entomol. 15: 507-512.
HARRIS, E. J., AND C. Y. L. LEE. 1987. Seasonal and an-
nual distribution of the Mediterranean fruit fly
(Diptera: Tephritidae) in Honolulu and suburban areas
of Oahu, Hawaii. Environ. Entomol. 16: 1273-1282.
HARRIS E. J., R. I. VARGAS, AND J. E. GILMORE. 1993.
Seasonality in occurrence and distribution of Medi-
terranean fruit fly (Diptera: Tephritidae) in upland
and lowland areas on Kauai, Hawaii. Environ. Ento-
mol. 22: 404-410.
HEATH, R. R., N. D. EPSKY, B. D. DUEBEN, AND W. L.
MEYER 1996. Systems to monitor and suppress Cer-
atitis capitata (Diptera: Tephritidae) populations.
Florida Entomol. 79: 144-153.
HENDRICKS, J., B. I. KATSOYANNOS, D. R. PAPAJ, AND R.
J. PROKOPY. 1991. Sex differences in movement be-
tween natural feeding and mating sites and
tradeoffs between food consumption, mating success
and predator evasion in Mediterranean fruit flies
(Diptera: Tephritidae). Oecologia (Berl.) 86: 223-231.


ISRAELY, N. B. YUVAL, U. KITRON, AND D. NESTEL. 1997.
Population fluctuations of adult Mediterranean fruit
fly (Diptera: Tephritidae) in a Mediterranean heter-
ogeneous agricultural region. Environ. Entomol. 26:
1263-1269.
KATSOYANNOS, B. I., N. A. KOULOUSSIS, AND J. R.
CAREY. 1998. Seasonal and annual occurrence of
Mediterranean fruit fly (Diptera: Tephritidae) on
Chios island, Greece: Differences between two
neighboring citrus orchards. Ann. Entomol. Soc.
America 91: 43-51.
LINARES, F., AND R. VALENZUELA. 1993. Medfly program
in Guatemala and Mexico: current situation, pp.
425-438 In M. Aluja, and P. Liedo [eds.], Fruit Flies:
Biology and Management. Springer-Verlag, NY.
LIQUID, N. J., L. A. SHINODA, AND R. T. CUNNINGHAM.
1991. Host plants of the Mediterranean fruit fly
(Diptera: Tephritidae): an annotated world review.
Misc. Publ. Entomol. Soc. America 77: 1-52.
MALAVASI, A., AND J. S. MORGANTE. 1981. Adult and lar-
val population fluctuation ofAnastrepha fraterculus
and its relationship to host availability. Environ. En-
tomol. 10: 275-278.
NEWELL, I. M., AND F. H. HARAMOTO. 1968. Biotic fac-
tors influencing populations ofDacus dorsalis in Ha-
waii. Proc. Hawaiian Entomol. Soc. 20: 81-139.
NISHIDA, T., E. J. HARRIS, R. I. VARGAS, AND T. T. Y.
WONG. 1985. Distributional loci and host fruit utili-
zation patterns of the Mediterranean fruit fly, Cer-
atitis capitata (Diptera: Tephritidae), in Hawaii.
Environ. Entomol. 14: 602-606.
OROZCO, D., W. R. ENKERLIN, AND J. REYES. 1994. The
Moscamed program: practical achievements and con-
tributions to science, pp. 209-222 In C. O.Calkins, W.
Klassen and P. Liedo [eds.], Fruit Flies and the Sterile
Insect Technique. CRC Press, Boca Raton, FL.
OVRUSKI, S., P. SCHLISERMAN, AND M. ALUJA. 2003. Na-
tive and introduced host plants ofAnastrepha frataer-
culus and Ceratitis capitata (Diptera: Tephritidae) in
northern Argentina. J. Econ. Entomol. 96: 1108-1118.
PAPADOPOULOS, N. T., J. R. CAREY, B. I. KATSOYANNOS,
AND N. A. KOULOUSSIS. 1996. Overwintering of the of
the Mediterranean fruit fly (Diptera: Tephritidae) in
northern Greece. Ann. Entomol. Soc. America. 89:
526-534.
PAPADOPOULOS, N. T., B. I. KATSOYANNOS, J. R. CAREY,
AND N. A. KOULOUSSIS. 2001. Seasonal and annual
occurrence of the Mediterranean fruit fly (Diptera:
Tephritidae) in northern Greece. Ann. Entomol. Soc.
America 94: 41-50.
PAPADOPOULOS, N. T. B. I. KATSOYANNOS, AND D. NES-
TEL. 2003. Spatial autocorrelation analysis of a Cera-
titis capitata (Diptera: Tephritidae) adult population
in a mixed deciduous fruit orchard in northern Greece.
Environ. Entomol. 32: 319-326.
PROKOPY R. J., AND B. D. ROITBERG. 1989. Fruit fly for-
aging behavior, pp 295-306 In A. S. Robinson and G.
Hooper [eds.], World Crop Pests. Fruit Flies. Their
Biology, Natural Enemies and Control, Vol. 3A.
Elsevier, Amsterdam.
PROKOPY, R. J., J. J. DUAN, AND R. I. VARGAS. 1996. Po-
tential for host range expansion in Ceratitis capitata
flies: impact of proximity of adult food to egg-laying
sites. Ecol. Entomol. 21: 295-299.
SAS INSTITUTE. 1998. Statview, user's reference man-
ual, 2nd ed. SAS Institute, Cary, NC.
SHELLEY, T. E., P. RENDON, E. HERNANDEZ, S. SAL-
GADO, D. MCINNIS, E. VILLALOBOS, AND P. LIEDO.







90 Florida Entc



2003. Effects of dyes, ginger root oil, and elevation
on mating competitiveness of male Mediterranean
fruit flies (Diptera: Tephritidae) from mass-reared
genetic sexing strain in Guatemala. J. Econ. Ento-
mol. 96: 1132-1141.
SEIBERT, J. B., AND V. PRADHAN. 1990.The potential eco-
nomic impact of the Mediterranean fruit fly Ceratitis
capitata (Wied.), upon establishment in California
(an update). Agricultural Resource Economics. Coop-
erative Extension. Univ. of California, Berkeley.
SIEGEL, S., AND N. J. CASTELLAN. 1988. Non-parametric
Statistics for the Behavioral Sciences. 2nd Ed.
McGraw Hill, Inc., NY.
SOUTHWOOD, T. R. E. 1978. Ecological Methods with
Particular Reference to the Study of Insect Popula-
tions. Chapman & Hall, U.K.


)m


ologist 88(1) March 2005



VARGAS, R. I. 1989. Mass production of tephritid fruit
flies, pp. 141-151 In A. S. Robinson and D. Hooper
[eds.], World Crop Pests. Fruit Flies: Their Biology,
Natural Enemies and Control, Vol. 3B. Elsevier,
Amsterdam.
VARGAS, R. I., E. J. HARRIS, AND T. NISHIDA. 1983. Dis-
tribution and seasonal occurrence of Ceratitis capi-
tata (Wiedemann) (Diptera: Tephhritidae) on the
island of Kauai in the Hawaiian Islands. Environ.
Entomol. 12: 303-310.
VAYSSIERES, J. F., AND Y. CAREL. 1999. Les Dacini
(Diptera: Tephhritidae) infeodes aux Cucurbitaceae
a la R6union: Gamme de plantes-hotes et states
ph6nologiques pr6fer6ntiels des fruits au moment de
la piqfire pour des especes cultivees. Ann. Soc. Ento-
mol. France 35: 197-202.







Jones & Gillett: Intercropping for Beneficial Insects


INTERCROPPING WITH SUNFLOWERS TO ATTRACT
BENEFICIAL INSECTS IN ORGANIC AGRICULTURE

GREGORY A. JONES'AND JENNIFER L. GILLETT2
'Department of Wildlife Ecology and Conservation
110 Newins-Ziegler Hall, University of Florida, Gainesville, FL 32611-0430

2USDA-ARS, Center for Medical, Agricultural and Veterinary Entomology, P.O. Box 14565, Gainesville, FL 32604

ABSTRACT
Sunflowers (Helianthus spp.) are listed in many extension factsheets and other such publi-
cations as excellent plants to attract beneficial insects in addition to those known to be im-
portant pollinators. We performed a 2-year study at a number of organic farms in Alachua
County, Florida to determine if the presence of sunflower rows included in a polyculture sys-
tem increased the occurrence and abundance of beneficial insects in cropped fields. The oc-
currence of beneficial insects was significantly greater on sunflower than on crop vegetation
in control blocks and crop vegetation greater than 10 m distant from sunflowers. While crop
vegetation 10 m distant from sunflowers harbored significantly fewer beneficial insects, this
difference in occurrence was not seen in crop vegetation 1 m distant from sunflowers. Our re-
sults indicate that sunflowers indeed attract and play host to numerous beneficial insects
suggesting that sunflower plantings within rows of vegetable crops may indeed be an effec-
tive way to attract beneficial insects into cropped fields. However, further study is required
to fully describe the distances key beneficial insects move from sunflowers and the impact
these beneficial insects have on crop pests.

Key Words: beneficial insects, sunflowers, insect diversity, intercropping, organic agriculture

RESUME

El girasol esta descrito en muchos folletos de extension agricola y otras publicaciones agricolas
como una plant excelente para atraer insects ben6ficos, ademas de incluir insects de impor-
tancia como los polinizadores. Nosotros realizamos un studio por un period de dos aios en
varias granjas organicas en el condado de Alachua en Florida para determinar si la presencia
del girasol sembrado en hileras en un sistema policultural aumentaria la presencia y la abun-
dancia de insects ben6ficos en campos sembrados. La ocurencia de insects ben6ficos fue mu-
cho mayor en el girasol que en el cultivo en los bloques de control y en las plants del cultivo
sembradas a mas de 10 m de distancia de las hileras de girasol. Aunque las plants del cultivo
sembradas 10 m del girasol fueron un refugio menos significativo para los insects ben6ficos,
esta diferencia no fue observada en plants del cultivo sembradas a 1 m de distancia del gira-
sol. Nuestros resultados indican que los girasoles en verdad atraen y juegan un papel como
hospederos a un gran numero de insects ben6ficos y se sugiere que la siembra del girasol en
hileras de cultivos vegetables en verdad pueden tener un efecto para atraer insects ben6ficos
dentro de los campos agricolas. Sin embargo, se require studios adicionales para determinar
las distancias de las species claves de insects ben6ficos que se mueven del girasol al cultivo
y el impact que tienen estos insects ben6ficos sobre las plagas en los cultivos.


Translation provided by the authors.


Insect predators and parasitoids of crop pests
can be influenced to take up residence within
cropping systems by providing habitat for them
(Helenius 1998). Farm management to enhance
the presence of beneficial insects refers to the es-
tablishment of food resources and habitat re-
quired by these species that increase and sustain
their populations (Pickett & Bugg 1998). Pollina-
tors and parasitoids can be attracted to cropped
fields by including nectar producing flowering
plants. For example the planting of sweet alys-
sum (Lobularia maritime Linnaeus) around cab-
bage fields is thought to increase longevity of
parasitic wasps that are beneficial in reducing


pest populations in the field (Johanowicz &
Mitchell 2000). These natural enemies can be at-
tracted to cropped areas and their numbers in-
creased by including within-field habitat strips,
select cover crops, and proper management of
field margins, hedgerows, fencerows, windbreaks,
irrigation and drainage ditches, and roadside
margins. For example, several studies have found
that sown weed strips within cropped areas in-
creased natural enemy abundance and activity in
crops by providing habitat for these enemies into
and throughout the interior of the cropped fields.
Additionally, rates of feeding of these natural en-
emies on pest insects were higher near the sown







Florida Entomologist 88(1)


weed strips (Nentwig 1998; Schoenig et al. 1998;
Wratten et al. 1998).
Sunflowers (Helianthus spp.) are listed in
many extension factsheets (Univ. of Florida Ex-
tension Circular 563, Univ. of Rhode Island Land-
scape Horticulture Factsheet, Univ. of Maine
Coop Extension Bulletin # 7150) and other such
publications (Long 1993; Starcher 1995; Turton
1998) as excellent plants to attract beneficial in-
sects such as those known to be important polli-
nators (e.g., honey bees and other bee species) or
known to prey upon or parasitize agricultural in-
sect pests (e.g., lacewings, big eyed bugs, ladybird
beetles, and numerous parasitoids). While infor-
mative, these particular extension publications
are directed to the home gardener describing how
to attract beneficial insects to their gardens.
Therefore, we wanted to test the effectiveness of
attracting beneficial with sunflower plantings in
a commercial cropping system context.
We performed a 2-year study at a number of or-
ganic farms in Alachua County, Florida to deter-
mine if the presence of sunflower rows included in
a polyculture system increased the occurrence
and abundance of beneficial insects in cropped
fields. In year one we compared the occurrence of
both beneficial and pest insects on intercropped
sunflowers to those occurring on paired crop veg-
etation in control plots. In year two we attempted
to determine whether predatory insects attracted
to the sunflower rows moved into adjacent crop
vegetation by compared the occurrence of benefi-
cial insects on sunflowers and crop vegetation ad-
jacent to sunflower plantings (within 1 m) to those
occurring on the same crop vegetation 10 m dis-
tant from sunflower rows.

MATERIALS AND METHODS

Research Site Selection

With the help of the director of the Florida Or-
ganic Growers Association, Marty Mesh, growers
were identified in North-central Florida during
the fall of 2001 and permission was obtained to
conduct research activities on their properties
during the course of our 2-year study. All partici-
pating farms were under certified organic man-
agement as designated by the Florida Organic
Growers Association (Florida Certified Organic
Growers and Consumers, Inc., PO Box 12311,
Gainesville, FL 32604) and most are now USDA
Organic certified.

Sunflower Intercrop Strips

Four growers were asked to incorporate rows
of multi-branched open-pollinating varieties of
sunflowers into their cropped acreage at the ear-
liest planting dates during their planting season
spring-summer 2002 and 2003. A total of 16 ten-


acre blocks were chosen for the study, 8 of which
received sunflower row treatment while the other
8 served as controls within the 4 participating
farms. On each farm one ten-acre block received a
treatment of 1 row per acre, another ten-acre
block received a treatment of 2 rows per acre and
each was paired with a control block. Sunflower
rows consisted of 1-m-wide rows of plants at a
density of approximately 9 plants per square
meter and were interspersed between, and paral-
lel with, production rows (Fig. 1). Sunflower rows
were maintained throughout the growing season
as other crops were planted, harvested, and ro-
tated through the acreage of each farm's produc-
tion area. Treatment and control blocks were also
paired by crop type, which included sweet corn,
collards, tomatoes, okra, and watermelon. Treat-
ment blocks were assigned different treatments
during the second field season.

Insect Surveys

During growing season 2002, insects were
sampled a minimum of 3 times in 10 randomly
chosen 1-m2 quadrats within sunflower rows con-
sisting of the sunflowers and crop vegetation (di-
rectly adjacent to sunflowers). Insects were also
sampled in 10 randomly chosen locations in con-
trol blocks of the paired crop vegetation. During
2003, insects were again sampled a minimum of 3
times in 10 randomly chosen 1-m2 quadrats
within sunflower rows, 10 quadrats in crop vege-
tation at 1 m, and 10 quadrats at 10 m distant
from the sunflower rows. Insects were sampled by
standard scouting techniques involving a sweep
net and a beat cloth, as well as examination of
each leaf and flower head occurring within each
quadrant and counting the numbers of individu-
als found per m2 of crop vegetation (after Morris
1960; Southwood 1978). Insects observed were
identified to family level and relative abundances
noted. For most of the insects sampled, identifica-
tion to family was followed by a quick ID to genus
or species level to determine if an insect was an
actual crop pest, benign, or beneficial according to
Henn et al. (1997) and the UF Coop. Ext. Service
Insect Identification Sheets SPSET 5 (1997).
Most of these IDs to genus were made in the field
to reduce the cost associated with further taxon-
omy. In our record keeping, it was noted where a
genus and or species occurred more frequently
then a counterpart organism from the same fam-
ily. Those records that are more accurate than
family taxonomy are shown in the tables and
their numbers are not combined with other mem-
bers within the same family. The occurrence and
number of individuals per m2 beneficial and pest
insects found upon sunflower plants and crop veg-
etation during the two growing periods was com-
pared with a univariate analysis of variance (Zar
1999).


March 2005







Jones & Gillett: Intercropping for Beneficial Insects


Fig. 1. Multi-branching sunflower varieties were planted at 1 or 2 rows per acre between vegetable rows to at-
tract birds and beneficial insects into cropped fields. A row of sunflowers is shown here planted between rows of
tomatoes.


RESULTS

Beneficial Insects

Beneficial insects were attracted to sunflower
plants by the time the plants reached 0.15 m in
height. Beneficial insects observed on sunflowers
and nearby crop vegetation (within 1 m of sun-
flowers) included arthropod predators, parasitic
wasps, and important pollinators representing 30
different families (Table 1). The most commonly
occurring beneficial insects observed on sunflow-
ers were big-eyed bugs (Geocoris spp.), honeybees
(Apis mellifera), green lynx spiders (Peucetia uiri-
dans), ants (Formicidae), and sphecid wasps
(Sphecidae). The most commonly occurring bene-
ficial insects observed on nearby crop vegetation
were green lynx spiders (Peucetia viridans), lady
beetles (Coccinellidae), big-eyed bugs (Geocoris
spp.), predatory stink bugs (Pentatomidae), and
assassin bugs (Reduviidae). The occurrence of
beneficial insects was greater on sunflower than
on crop vegetation in control blocks in 2002 (F1,16 =
11.78, P = 0.003; Fig. 2) and crop vegetation


greater than 10 m distant from sunflowers in
2003 (F,,, = 12.94, P = 0.002; Fig. 3). While crop
vegetation 10 m distant from sunflowers har-
bored significantly fewer beneficial insects, this
difference in occurrence in sunflower and crop
vegetation was not seen in crop vegetation 1 m
distant from sunflowers when this was assessed
during the 2003 growing period (F,22 = 2.29, P =
0.144; Fig. 3).

Pest Insects

Pest insects representing 12 different arthro-
pod families were found on sunflowers and
nearby crop vegetation (Table 2). The most com-
monly occurring pest insects were green stink
bugs (Acrosternum hilare), corn flea beetles (Cha-
etocnema pulicaria, Chrysomelidae) and im-
ported cabbageworm larvae (Pieris rapae),
respectively. The occurrence of pest insects on
sunflower and crop vegetation in control plots did
not differ in 2002 (F,,, = 0.12, P = 0.74; Fig. 4) but
did differ in 2003 (F,,, = 14.7, P = 0.001; Fig. 5).
Greater mean numbers of pest insects per meter







Florida Entomologist 88(1)


March 2005


TABLE 1. BENEFICIAL INSECTS THAT WERE OBSERVED TO OCCUR IN RANDOMLY PLACED 1-M SCOUTING PLOTS ON SUN-
FLOWER AND NEARBY CROP VEGETATION (WITHIN 1 M OF SUNFLOWERS) DURING SPRING GROWING SEASONS
2002 AND 2003. BENEFICIAL INSECTS INCLUDED ARTHROPOD PREDATORS, PARASITIC WASPS, AND IMPORTANT
POLLINATORS REPRESENTING 30 DIFFERENT FAMILIES.

Family Common name Benefit

Anthocoridae Pirate Bugs Predator
Apidae Honey Bees Pollinator
Asilidae Robber Flies Predator
Cantharidae Soldier Beetles Predator
Chrysididae Cuckoo Wasps Predator
Coccinellidae Lady Beetles Predator
Danaidae Milkweed Butterflies Pollinator
Dermaptera Earwigs Predator
Eulophidae Eulophid Wasps Parasite
Formicidae Ants Predator
Gelastocoridae Big-eyed Bugs Predator
Halictidae Green Metallic Bees Pollinator
Hesperiidae Skippers Pollinator
Ichneumonidae Parasitic Wasps Parasite
Lycaenidae Gossamer-winged Butterflies Pollinator
Mordellidae Tumbling Flower Beetles Predator
Mutillidae Velvet-ants Predator
Mymaridae Mymarid Wasps Parasite
Oxyopidae Lynx Spiders Predator
Papilionoidae Swallowtail Butterflies Pollinator
Pentatomidae Predatory Stink Bugs Predator
Plutellidae Diamond-backed Moths Pollinator
Reduviidae Assassin Bugs Predator
Scarabaeidae Scarab Beetles Predator
Sphecidae Sphecid Wasps Parasite
Tenebrionidae Darkling Beetles Predator
Thomisidae Crab Spiders Predator
Tiphiidae Tiphiid Wasps Parasite
Trichogrammatidae Trichogrammatid Wasps Parasite
Vespidae Vespid Wasps Parasite


were observed on sunflower vegetation than on
crop vegetation greater than 10 m distant from
sunflowers (2.5 individuals/m2 vs. 0.2 individuals/
m2, respectively). This same difference was found


4.0-


-0-


Crop Vegetation


Sunflowers


Fig. 2. Occurrence of beneficial insects was greater
on sunflower vegetation than on crop vegetation during
the 2002 growing season (F,,1 = 11.78, P = 0.003). Error
bars = 1 SE.


Distant Adjacent Sunflowers
l m >1m

Fig. 3. The occurrence of beneficial insects was
greater on sunflower vegetation than on crop vegetation
more than 10 m distant from sunflowers in 2003 (F,16 =
12.94, p = 0.002). Occurrence of beneficial insects on
crop vegetation 1 m distant from sunflowers did not sig-
nificantly differ from that found on sunflower vegeta-
tion (F1,22 = 2.29, P = 0.144). Error bars = 1 SE.







Jones & Gillett: Intercropping for Beneficial Insects


TABLE 2. PEST INSECTS THAT WERE OBSERVED TO OCCUR IN RANDOMLY PLACED 1-M SCOUTING PLOTS ON SUNFLOWER
AND NEARBY CROP VEGETATION (WITHIN 1 M OF SUNFLOWERS) DURING SPRING GROWING SEASONS 2002 AND
2003. INSECTS OBSERVED ARE LISTED IN ORDER OF RELATIVE ABUNDANCE.

Family Common name Pest problem

Aphidae Aphids Disease transmission
Aleyrodidae White flies Disease transmission
Pentatomidae Stinkbugs Feeding damage
Chrysomelidae Plant Beetles Feeding damage
Lygidae Plant bugs Feeding damage
Coreidae Plant bugs Feeding damage
Cicadellidae Leafhoppers Disease transmission
Noctuidae Armyworms Feeding damage
Pieridae Cabbageworms Feeding damage
Plutellidae Diamondback moths Feeding damage
Sphingidae Sphinx moths Feeding damage


on crop vegetation within 1 m of sunflowers as
well in 2003 (2.5 individuals/m2 vs. 0.5 individu-
als/m2, respectively, F,22 = 13.4, P = 0.001; Fig. 5).

DISCUSSION

In this study we found that diversity and abun-
dance of beneficial insects increased in crop vege-
tation directly adjacent to sunflower rows. Our
scouting efforts revealed that sunflowers did in-
deed attract and play host to numerous beneficial
insects as has been described in numerous publi-
cations. Sunflower plants were found to attract
predaceous insects almost immediately after es-
tablishment when sunflower plants reached a
minimum height of 6 inches. Parasitoids and pol-
linators were attracted as soon as these plants be-
gan to produce flowers. Some of the same
beneficial insects were found also to occur on crop


2.50-


2.00-


1.50-


1.00-


0.50-


Crop Vegetation Sunflowers

Fig. 4. Occurrence of pest insects on sunflower and
crop vegetation in control plots did not differ in 2002
(F16, = 0.12, P = 0.74). Error bars = 1 SE.


vegetation but in significantly lower numbers. It
has been found in several studies that providing
predator refugia within cropping systems via
strip crops or uncultivated corridors can result in
the migration of predatory insects into adjacent
crops (see Johanowicz & Mitchell 2000; Mensah
1999; Nentwig 1998; Schoenig et al. 1998; Wrat-
ten et al. 1998; Rodenhouse et al. 1992). In the
2003 growing season, we modified the sampling
methodology in an attempt to determine whether
beneficial insects attracted to the sunflowers may
have been moving out from the sunflowers into
adjacent crop vegetation. Results indicated that
crop vegetation within 1 m of sunflowers exhib-
ited nearly the same abundance and diversity of
beneficial insects as did the sunflowers them-



3.00 -


2.00 -



1.00 -


0.00 -
Distant Adjacent Sunflowers
10m > Im

Fig. 5. Occurrence of pest insects on sunflower and
crop vegetation greater than 10 m distant from sunflow-
ers differed in 2003 (F,1, = 14.7, P = 0.001). Greater
mean numbers of pest insects per meter were observed
on sunflower vegetation than on crop vegetation greater
than 10 m distant from sunflowers (2.5 individuals/m2
vs. 0.2 individuals/m2, respectively). This same differ-
ence was found on crop vegetation within 1 m of sun-
flowers as well (2.5 individuals/m2 vs. 0.5 individuals/
m2,respectively, F,22 = 13.4, P = 0.001).











selves. However, crop vegetation 10 m distant
from sunflowers harbored significantly fewer ben-
eficial insects than did that within 1 m. Further
study is required to fully describe the distances
key beneficial insects move from sunflowers and
the impact these beneficial insects have on crop
pests. However, results of this study suggest that
sunflower plantings within rows of vegetable
crops may indeed be an effective way to attract
beneficial insects into cropped fields.

ACKNOWLEDGMENTS
The Organic Farming Research Foundation, Santa
Cruz, CA provided funding for this research. We are
truly grateful for the collaborative assistance of the fol-
lowing researchers: Dr. Kathryn E. Sieving and Dr.
Kenneth Buhr and logistic cooperation of Marty Mesh
and the Florida Certified Organic Growers and Con-
sumers, Inc. The cooperation and participation of the
following producers is gratefully acknowledged as well:
Lois Milton, Tommy Simmons, Bill Ogle, Bill Allen, Ro-
salie Koenig, Donald Appelbaum, Charles Andrews, and
Joe Durando. This is Florida Agricultural Experiment
Station Journal Series R-10617.

LITERATURE CITED

BUCHMANN, S. L., AND G. P. NABHAN. 1997. The Forgot-
ten Pollinators. Island Press, Washington, DC.
GRISSEL, E. 2001. Insects and Gardens: In Pursuit of
Garden Ecology. Timber Press, Portland, OR.
HELENIUS, J. 1998. Enhancement of predation through
within-field diversification, pp. 121-160 In C. H.
Picket and R. L. Bugg [eds.], Enhancing Biological
Control. University of California Press, Berkeley.
HENN, T., R. WEINZIERL, AND P. G. KOEHLER 1997. Ben-
eficial Insects and Mites. Cooperative Extension Ser-
vice Document ENY-276, Institute of Food and
Agricultural Sciences, Univ. of Florida, Gainesville.
JOHANOWICZ, D. L., AND E. R. MITCHELL. 2000. Effects
of sweet alyssum flowers on the longevity of the par-
asitoid wasp Cotesia marginiventris (Hymenoptera:
Braconidae) and Diadegma insulare (Hymenoptera:
Ichneumonidae). Florida Entomol. 83(1): 41-47
MENSAH, R. K. 1999. Habitat diversity: implications for
the conservation and use of predatory insects of
Helicoverpa spp. in cotton systems in Australia. Int.
J. Pest Manage. 45: 91-100.


March 2005


MORRIS, R. F. 1960. Sampling insect populations. Annu.
Rev. Entomol. 5: 243-264.
NENTWIG, W. 1998. Weedy plant species and their ben-
eficial arthropods: potential for manipulation in field
crops, pp. 49-73 In C. H. Picket and R. L. Bugg [eds.],
Enhancing Biological Control. Univ. of California
Press, Berkeley.
PICKET, C. H., AND R. L. BUGG. 1998. Introduction: en-
hancing biological control-habitat management to
promote natural enemies of agricultural pests, pp. 1-
24. In C. H. Picket and R. L. Bugg [eds.]. Enhancing
Biological Control. Univ. of California Press, Berke-
ley.
RODENHOUSE, N. L., G. W. BERRETT, D. M. ZIMMERMAN,
AND J. C. KEMP. 1992. Effects of uncultivated corri-
dors on arthropod abundances and crop yields in
soybean agroecosystems. Agric., Econ., and Environ.
38: 179-191.
SCHOENIG, S. E., R. L. BUGG, AND J. UTTS. 1998. The
role of experimentation in the development of en-
hancement strategies, pp. 271-298 In C. H. Picket
and R. L. Bugg [eds.], Enhancing Biological Control.
Univ. of California Press, Berkeley.
SOUTHWOOD, T. R. E. 1978. Ecological Methods. Chap-
man and Hall Publishers, London, UK.
STARCHER, A. M. 1995. Good Bugs for your Garden. Al-
gonquin Books of Chapel Hill, Chapel Hill.
TURTON, D. 1998. Attracting beneficial insects. http://
www.i5ive.com/article.cfm/organic_gardening/10893.
UNIVERSITY OF FLORIDA COOPERATIVE EXTENSION.
1992. Insect management and control in the home
garden. Circular 563. Institute of Food and Agricul-
tural Sciences, Univ. of Florida, Gainesville.
UNIVERSITY OF FLORIDA COOPERATIVE EXTENSION.
2000. Insect Identification Sheets SPSET5: Com-
plete set. Fact Sheets. Institute of Food and Agricul-
tural Sciences, Univ. of Florida, Gainesville.
UNIVERSITY OF RHODE ISLAND LANDSCAPE HORTICUL-
TURE. 2001. Beneficial insects in the garden. Pro-
gram Factsheet. http://www.uri.edu/factsheets/sheets/
beneficialinsects.html.
UNIVERSITY OF MAINE COOPERATIVE EXTENSION. 2001.
Beneficial insects in your backyard. Bulletin #7150.
http://www.umext.maine.edu/onlinepubs/htmpubs/
habitats/7150.htm.
WRITTEN, S. D., H. F. VAN EMDEN, AND M. B. THOMAS.
1998. Within-field and border refugia for the en-
hancement of natural enemies, pp. 375-404 In C. H.
Picket and R. L. Bugg [eds.]. Enhancing Biological
Control. Univ. of California Press, Berkeley.


Florida Entomologist 88(1)







Scientific Notes


HOST SUITABILITY OF SELECTED FICUS SPECIES
FOR THRIPS PALMI (THYSANOPTERA: THRIPIDAE)

CHERYLE A. O'DONNELL AND MICHAEL P. PARRELLA
University of California, Davis, One Shields Avenue, Davis, CA 95616


The melon thrips, Thrips palmi (Karny) (Thys-
anoptera: Thripidae), which is a pest on many or-
namentals (Faust et al. 1992) and a known virus
vector (Iwaki et al. 1984), probably originated in
Southeast Asia (Girling et al. 1992). In the United
States, it is reported from Florida and Hawaii,
and since 1991, south Florida has experienced
problems with T palmi on potatoes, eggplant,
bush beans, bell peppers, and yellow squash
(Girling et al. 1992). It has a large host range of
over 50 plant species (Dentener et al. 2002), of
which eggplants and orchids are among the pre-
ferred hosts. Although not a problem on Ficus in
Florida, T palmi was reportedly intercepted in
1992 on Ficus benjamin cultivars from Florida
in the Netherlands (Parrella & Mound 1998; Vier-
bergen 1996). Whether this was simply inciden-
tal, or whether T palmi can use Ficus as a host
plant for feeding and reproduction is unclear.
In this study we determine the suitability of
Ficus cultivars as host plants for T palmi com-
pared to known host plants: Dendrobium orchids
(Hata et al. 1991) and eggplant (Kitamura &
Kawai, 1983), and record the presence/absence of
T palmi in a production Ficus nursery in Home-
stead, Florida, and surrounding areas. Experi-
ments were conducted from October 1997 through
March 1998 in a lab and an 8.08 hectare outdoor
nursery planted with 4 Ficus spp. cultivars as
rootstocks and 7 Ficus spp. in pots. The nursery
was adjacent to a field planted with yellow squash
from October to December 1997, and bush beans
from January to February 1998. Weather param-
eters were recorded from the local Homestead
weather station throughout the experiment.
To determine the host suitability, adult females
of T palmi were placed onto Ficus benjamin 'Mo-
nique', Selanum melogena (eggplant) and a Den-
drobium orchid cultivar in no-choice tests and
eclosion of larvae was monitored. Thrips used for
these experiments were collected from cucumber
and eggplant in southern Florida and reared on
eggplant in a greenhouse. Individual plant sleeves
(0.05 cm Reemay spun bound polyester; Kleen
Test, Milwaukee, WI) were placed over 6 eggplant
plants and 6 orchid flower spikes, with 2 sleeves
fitted on to 2 plants or spikes containing no thrips
(control) and 4 sleeves fitted on to 4 plants or
spikes containing 10 adult female thrips. Each of 3
Ficus plants had 2 control sleeves with no thrips
and 4 sleeves containing 10 adult female thrips
per sleeve placed over individual stems. The mesh
sleeves retained thrips on the plants although
movement was not hindered. All adult thrips were


counted and removed from each sleeve after 5
days, and eclosion of larvae was assessed by daily
visual examination over the next 21 days. This ex-
periment was replicated three times. Plants were
kept in a lab maintained at 24C with continuous
fluorescent lighting. The average number ofthrips
larvae per plant/per day/plant species was com-
pared across the three plant species by one-way
ANOVA and Dunn's pairwise comparisons test at
0.05 level of significance.
The presence ofthrips was recorded on 11 Ficus
cultivars planted as rootstock or in pots in the out-
door nursery. Twenty Ficus plants were randomly
selected and thrips were collected at weekly inter-
vals by beating branches (3 strikes per branch; one
branch per tree) over a white tray. In addition,
twenty-five yellow sticky traps (SeaBright Labora-
tories, Emeryville, CA) (10.16 x 17.78 cm), set at
1 m above the ground, were placed throughout the
nursery and replaced at weekly intervals over a
14-week period. The numbers and identities of
thrips collected on each trap were recorded weekly.
The field adjacent to the Ficus nursery, as well
as 10 fields containing bush beans, eggplant and
squash within a 16 km radius of the nursery, were
monitored weekly by visually inspecting 10 ran-
domly selected plants within each field and re-
cording the total count of T palmi.
Thrips were slide-mounted and identified to
species level with keys (Mound and Marullo 1996,
Nakahara 1994, Bailey 1957) and deposited in
the Bohart Museum of Entomology, UC Davis.
Ficus benjamin did not support reproduction
ofT. palmi (H = 172.9, df= 2, P = <0.0001) (Fig. 1).
Eggplant (SEM = 4.43) supported significantly
higher numbers of larvae than Dendrobium or-
chids (SEM = 1.87). Similarly, no live adult thrips
were found on Ficus, whereas adult thrips were
found alive on eggplant seedlings and orchid spikes
(1-2 adults per sleeve/plant). Thrips palmi was not
observed on the control eggplants, orchids or Ficus,
although thrips could move through the mesh.
Numbers of T palmi collected on sticky traps
were low throughout the experiment, and only one
adult was collected from the beating samples. Fif-
teen individuals of T palmi were collected on cu-
cumbers in a field approximately 16 km north of the
nursery. Thrips palmi was not collected in weekly
inspections of bush bean, eggplant, or squash fields.
Individuals of T palmi on sticky traps in the
nursery may have been dispersing adults from
nearby vegetable fields. Thrips palmi is usually
abundant on eggplant, bush beans, peppers, and
potatoes from September to April (Frantz et al.







Florida Entomologist 88(1)


-Orchid


5 6 7 8 9 D II 12 13 4 5I 16 1T I 19 29 21
No. dJs ptsu nrvlk c l Thripj pdwrjimnw plimnt slewcs..

Fig. 1. The average number of larvae of Thrips palmi
found per day/plant on 3 different host species. Num-
bers are based upon the average of three experiments
for a total of 6 eggplants, 6 orchids, and 3 Ficus plants,
with 6 sleeved replicates each. Standard error bars are
shown for each plant type.


1995; Seal 1997). The low number of T palmi col-
lected throughout the experimental period may
reflect low populations that only began to build up
in vegetable fields late in the season. In fact, po-
tato fields 12 km southeast of the nursery became
heavily infested with T palmi in late March 1998.
We gratefully acknowledge Miami Agra-Starts
for the use of their facilities, and we thank the re-
viewers from Florida Entomologist for comments
that helped improve this manuscript. Funding
was provided by the Ficus Growers Association of
Florida and the Netherlands and by the American
Floral Endowment.


NMiXm -arrT, iml -W*--yw Hh Tetmp C - W" Lw s Tlap t(


12-~---b


U


liii


II.e
*


Dale: Oct IW7 to March 1998
Fig. 2. Total number of Thrips palmi collected
weekly on all 25 sticky traps at the Ficus ~i-.... .. I. *
and temperature (solid line = high temp., dotted line =
low temp.) taken from the weather station in Home-
stead, Florida, throughout the 14 weeks. The stippled
area indicates the range of temperature that Teramoto
et al. (1982) reported as the preferred egg-laying tem-
perature for Thrips palmi. During the experiments, the
average relative humidity ranged from 72-84% and the
average precipitation from 0-11.91 cm per week. The av-
erage weekly low and high temperatures ranged from
12-22 C and 20-29 C, respectively.


-Eufpi..1


March 2005


SUMMARY

Ficus was shown to be an unsuitable host for
T palmi because thrips confined to Ficus benjam-
ina in a greenhouse produced no eggs, and no lar-
vae, and only one adult of T palmi was found on
Ficus plants in the nursery, despite the presence of
thrips on sticky cards. In contrast, eggs and larvae
of T. palmi were detected on eggplant and orchid
control plants in the greenhouse. Thus, T. palmi is
likely a casual visitor when found on Ficus.

REFERENCES CITED

BAILEY, S. F. 1957. Thrips of California Part I: Suborder
Terebrantia. Bulletin of the California Insect Sur-
vey. University of California Press Berkeley and Los
Angeles (5): 1-220.
DENTENER, P. R., D. C. WHITING, AND P. G. CONNOLLY.
2002. Thrips palmi Karny (Thysanoptera: Thripi-
dae): Could it survive in New Zealand? New Zealand
Plant Protection 55: 18-24.
FAUST, R. M., R. M. BARANOWSKI, J. R. COPPEDGE, AND
H. DENMARK. 1992. Thrips palmi working group/
ARS workshop report and action plan. Homestead
Florida November 20-21, 1991. United States De-
partment of Agriculture, Agricultural Research Ser-
vice April 1-20.
FRANTZ, G., F. PARKS, AND H. C. MELLINGER 1995.
Thrips population trends in peppers in southwest
Florida, pp. 111-114 In B. L. Parker [ed.], Thrips Biol-
ogy and Management. Plenum Press, New York.
GIRLING, D. G., L. A. MOUND, G. J. DUHEAUME, AND
A. K. WALKER [Eds.]. 1992. Thrips palmi a literature
survey with an annotated bibliography. CAB Inter-
national 1-37.
HATA, T. Y., A. H. HARA, AND J. D. HANSEN. 1991. Feed-
ing preferences of melon Thrips palmi on orchids in
Hawaii. HortScience 26(10): 1294-1295.
IWAKI, M., Y. HONDA, K. HANADA, H. TOCHIHARA, T. YO-
NAHA, K. HOKAMA, AND T. YOKOYAMA. 1984. Silver
mottle disease of watermelon caused by tomato spot-
ted wilt virus. Plant Disease 68: 1006-1008.
KITAMURA, C., AND A. KAWAI. 1983. Studies on popula-
tion ecology of Thrips palmi Karny 2, population
growth and distribution on eggplant in the field. Proc.
Association for Plant Protection of Kyushu 29: 85-87.
MOUND, L. A., AND R. MARULLO. 1996. The thrips of
Central and South America: And Introduction.
Memoirs on Entomology, International 6: 1-488.
NAKAHARA, S. 1994. The Genus Thrips Linnaeus (Thys-
anoptera: Thripidae) of the world. USDA technical
Bulletin 1822: 1-183.
PARRELLA, M. P., AND L. A. MOUND. 1998. November.
Making an example of Dutch Ficus growers. Grower-
Talks 34-40.
SEAL, D. R. 1997. Management and biology of Thrips
palmi Karny (Thysanoptera: Thripidae). New devel-
opments in Entomology 161-181.
TERAMOTO, S., K. NONAKA, AND K. NAGAI. 1982. Ecology
and control of thrips infesting fruit and vegetables,
part 6 protective potential of Thrips palmi. Proc.As-
sociation for Plant Protection of Kyushu 28: 128-129.
VEIRBERGEN, G. 1996. After Introduction of Franklin-
iella occidentalis in Europe: Prevention of establish-
ment of Thrips palmi (Thysanoptera: Thripidae).
Acta Phytopatholigica Hungarica 31(3-4): 267-273.







Scientific Notes


NEW FLIGHT DISTANCE RECORDED FOR
COPTOTERMES FORMOSANUS (ISOPTERA: RHINOTERMITIDAE)

MATTHEW T. MESSENGER' AND AARON J. MULLINS2
1Dow AgroSciences LLC, 6650 Fleur de Lis #9, New Orleans, LA 70124, USA

2City of New Orleans Mosquito & Termite Control Board
6601 Stars and Stripes Boulevard, New Orleans, LA 70126, USA


The Formosan subterranean termite (FST),
Coptotermes formosanus Shiraki (Isoptera: Rhino-
termitidae), was first introduced to New Orleans
after World War II inside infested cargo returning
from the Orient (La Fage 1987). For the past 60
years, they have spread throughout the New Or-
leans metro area, displaced native subterranean
termite species, and significantly damaged build-
ings, trees, boats, and railroad ties in the process.
To help combat the problem, the U.S. Department
of Agriculture-Agricultural Research Service
(USDA-ARS) provided funding for treating build-
ings in a 50-block area of the French Quarter in
New Orleans to determine if an area-wide subter-
ranean termite control program is capable of re-
ducing overall populations. Since 1998, populations
have been reduced based on structural inspec-
tions, termite activity inside independent moni-
toring stations installed throughout the French
Quarter, and the overall number of alates (winged
reproductive) recovered from insect glue boards
attached to streetlights throughout the French
Quarter (Lax & Osbrink 2003). However, alates
are still being captured in significant numbers in-
side selective areas of the French Quarter and
along the borders of this treatment zone.
Each year during May and June, untold num-
bers of male and female alates disperse through-
out the area in the early evening and tend to
congregate around light sources when present. In-
formation on how far they are capable of flying
from a dispersal point was virtually unknown, es-
pecially in a large urban area. During field obser-
vations in early 2004, it appeared that FST alates
were flying across the Mississippi River with the
aid of prevailing winds and into the French Quar-
ter. To establish if alates were dispersing into the
treatment zone from bordering areas, alates were
marked with fluorescent visible powders (Shan-
non Luminous Materials, Inc., Santa Ana, CA)
during two dispersal flights on different evenings
at a selected site of known termite activity across
the Mississippi River, located directly to the south-
east of the French Quarter. In cooperation with
USDA-ARS, 445 rectangular (20.7 cm x 10.2 cm)
glue boards (TRAPPER LTD, Bell Laboratories,
Inc., Madison, WI) were attached to streetlights
along the Riverwalk and throughout the French
Quarter to capture potentially marked alates. The
glue boards were positioned on the streetlights
just below the lantern. Weather conditions, includ-


ing wind velocity and direction, were recorded
each evening with a hand-held weather station
(Kestrel 4000, Nielsen-Kellerman, Boothwyn,
PA). Alates were individually marked with a
bright orange fluorescent powder with a hand-
held commercial duster as they were flying in a
north to northwest direction over the river. These
alates were already in flight at the time of mark-
ing and their source could not be located. After
marking, every glue board was removed and in-
spected with a UV black light. New glue boards
were used for each dispersal flight event.
On 1 June 2004, approximately 50 FST alates
were initially marked and a single alate was re-
covered across the River on a glue board 771 m
away (Fig. 1). Then, on 7 June, approximately 50
alates were marked again and two alates were re-
covered on glue boards 866 m and 892 m away
(Fig. 1). The wind direction on 1 and 7 June was
from the south and southeast at an average speed
of 0.93 m/sec and 0.83 m/sec, respectively. Previ-
ously, a wind speed at or below 1.0 m/sec was
shown to be one of the most important microenvi-
ronmental factors involved in determining dis-
persal flight activity (Leong et al. 1983).


Fig. 1. Flight distances of three Formosan subterra-
nean termite alates during dispersal flights across the
Mississippi River in early June 2004 (Source of color-in-
frared photograph: National Aerial Photography Pro-
gram, Jan. and Feb. 1998; courtesy of 3001-The Spatial
Data Company).







Florida Entomologist 88(1)


Historically, the only documented standard for
maximum FST dispersal was a horizontal flight
distance of 460 m at 2.2 m/sec (Ikehara 1966).
These alates were visually observed in a large
courtyard-type area located in Japan. Other stud-
ies have shown that the FST is capable of infesting
high-rise buildings (>40 m high) with the aid of
ocean current winds (Su et al. 1989). However, the
accepted horizontal dispersal distance for the FST
has always been approximately 100 m (Higa &
Tamashiro 1983). Our results show that the FST
is capable of flying almost twice the standard max-
imum (460 m) distance. At the same time, alates
were able to fly across the Mississippi River with
the aid of low wind speeds (<1 m/sec). These data
have shown how re-colonization is possible in a
treatment zone, such as the French Quarter in
New Orleans, particularly during FST dispersal
flight activity. In addition, these data represent an
important factor to consider when evaluating an
area-wide termite treatment project.
We are grateful to M. K. Carroll and C. Riegel,
New Orleans Mosquito and Termite Control
Board, for reviewing the manuscript. Special
thanks to Dennis Ring and Pedro Levy (Louisiana
State University Agricultural Center) for provid-
ing access to Operation Full Stop glue boards. We
are also grateful to Nan-Yao Su, University of
Florida, for reviewing the manuscript and trans-
lation of the Japanese reference. Partial funding
for this project was provided by USDA-ARS under
the grant agreement No. 58-6435-8-108.

SUMMARY
Results from two separate mark-recapture
trials revealed that Formosan subterranean ter-


mite, Coptotermes formosanus Shiraki
(Isoptera: Rhinotermitidae), alates are capable
of flying nearly one kilometer across the Missis-
sippi River and into the historic French Quarter.
This is the first documented mark-recapture
study with alates on this scale, and our results
represent a new C. formosanus flight distance
record.

REFERENCES CITED
HIGA, S. Y., AND M. TAMASHIRO. 1983. Swarming of the
Formosan subterranean termite, Coptotermes for-
mosanus Shiraki, in Hawaii (Isoptera: Rhinotermiti-
dae). Proc. Hawaii Entomol. Soc. 24: 233-238.
IKEHARA, S. 1966. Research report, pp. 49-178. Bull.
Arts Sci. Div., Ryukyu University, Naha, Okinawa,
Japan (in Japanese).
LA FAGE, J. P. 1987. Practical considerations of the For-
mosan subterranean termite in Louisiana: A 30-year
problem, pp. 37-42 In N.-Y. Su and M. Tamashiro
[eds.]. Biology and Control of the Formosan Subter-
ranean Termite. College of Trop. Agr. Human Re-
sources, Univ. of Hawaii, Honolulu, HI.
LAX, A. R., AND W. L. OSBRINK. 2003. United States De-
partment of Agriculture-Agricultural Research Ser-
vice research on targeted management of the
Formosan subterranean termite Coptotermes formo-
sanus Shiraki (Isoptera: Rhinotermitidae). Pest
Manag. Sci. 59: 788-800.
LEONG, K. L. H., M. TAMASHIRO, M., J. R. YATES, AND
N.-Y. Su. 1983. Microenvironmental factors regulat-
ing the flight of Coptotermes formosanus Shiraki in
Hawaii (Isoptera: Rhinotermitidae). Proc. Hawaii
Entomol. Soc. 24: 287-291.
Su, N.-Y., R. H. SCHEFFRAHN, AND P. M. BAN. 1989.
Method to monitor initiation of aerial infestations by
alates of the Formosan subterranean termite
(Isoptera: Rhinotermitidae) in high-rise buildings. J.
Econ. Entomol. 82: 1643-1645.


March 2005




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