Title: Florida Entomologist
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Permanent Link: http://ufdc.ufl.edu/UF00098813/00134
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Title: Florida Entomologist
Physical Description: Serial
Creator: Florida Entomological Society
Publisher: Florida Entomological Society
Place of Publication: Winter Haven, Fla.
Publication Date: 1974
Copyright Date: 1917
Subject: Florida Entomological Society
Entomology -- Periodicals
Insects -- Florida
Insects -- Florida -- Periodicals
Insects -- Periodicals
General Note: Eigenfactor: Florida Entomologist: http://www.bioone.org/doi/full/10.1653/024.092.0401
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Volume ID: VID00134
Source Institution: University of Florida
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Volume 57, No. 1 March, 1974


MUCHMORE. W. B.-Pseudoscorpions from Florida. I The Genus Allda
hn rn s (Pseudoscorpionida: Olptidae) .. 1
NICKLE D. A., AND T. J. WALKER-A Morphological Key to Field Cricket.
'f Southeastern United States (Orthoptera:Gryllidae:Grilus) .. 8
WALKER, T. J.-Gryllus ovisopis N.Sp.. A Taciturn Cncket with a life Cycle
Suggesting A llochronic Speciation ...... . 13
WIRTH, W. W., AND F. S. BLANTON-A New Florida Sand Fly Closely Re-
lated to Culicoides haematopotus Malloch (Diptera: Ceralopogo-
nidae) ... .. ........... 23
DILBECK, J. D., J. W. TODD. AND T. D. CANERDAY--Pckleworm Resistance
in Cucurbita 27
GREENE, G. L., AND M. SHEPA.RD-Biologicul Studies of a Predator, Sy-
canus indigator. 11. Field Suriwual and Predation Potential .. 33
MORRILL, W. L.-Dispersaol of Red Imported Fire Ants by Water .. 39
LEVY, R., H. L. CROMROY, AND J. A CORNELL--Multi-Elemental Models
for Estimating the Acute Radiosensitwily of Cockroaches and Blood
Feeding Insects .... 43
SABA, F.-Life History and Population Dynamics of Tetranychus tumidus
in Florida (4canna:Tetranychdae .. 47
FATZINGER, C. W.-Extraction of Feeding Stimulants from Slash Pine
Cones for Larvae of Dioryctria abietella 65
WIRTH, W. W., AND F. S. BLANTON--NeC S.\nonom\ and a Correction in
the Culicoides piliferus Group (Dipteru: ('eratopoigonidr i .. . 71
MUCHMORE, W. B.-Pseudoscorpionr. fr,,m Flortdla 2 .4 Newu Genus and
Species Bituberochernes mum ae Chetrnetidae) 77
STEGMAIER, C. E., JR., AND H. R. BURKE-Anthonomus flavus IColeop-
tera:Curculionidae) .4 Fruit Inlf-.,Itng lWerl' ,f the Brhbudo.l Cherry,
Malpighia glabra ilalpighuacjacl. 'cu i ,iNorth .-i erica 81
BROWER. J. H.-Radtio,en.ittit i.t of the Slenderhorned Flour Beetle.
Gnathocerus maxillosus ( Cohlptieru Ttenebrionicdae) 91
HaRRIS. D. L.. AND W. H. WmHrcoMB-Effects of Fire on Populationls of
Certaini S peefs of Ground Beetles (Colhoptera C'rabidac) 97
GREENBAUM, H. N.-A New Xyela (Hymenoptera: Xyelidae) from Florida............ 104
Notice of New Features in The Florida Entomologist ........-.................... ..... ........ 7
N otes and A bstracts .......................................................... ............... 22, 32, 38, 46, 90, 96
Book Review ........ ... ..... ................................................................... . . . . . ... 107
Editorial: Acceptable Manuscripts for The Florida Entomologist .......................... 109

Published by The Florida Entomological Society



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Vice-President ................................ R. M. Baranowski
S secretary .............................. ........................... ............... .................... F W M ead
Treasurer ................................................ D. E. Short

C. S. Lofgren
W. G. Eden
Other Members of Executive Committee........ A. Sehime
H. D. Bowman
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Associate Editors .............................................. R. E. Woodruff
R. C. Wilkinson
H. V. Weems, Jr.
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THE FLORIDA ENTOMOLOGIST is issued quarterly-March, June, September, and
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Entered as second class matter at the post office at Gainesville, Florida.
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This issue mailed May 3, 1974



Department of Biology, University of Rochester
Rochester, New York 14627


An emended diagnosis of the genus Aldabrinus is given; the holotype of the
type species, A Idabrinus aldabrinus Chamberlin, from the Aldabra Islands, is
redescribed; and Aldabrinus floridanus, from Key Largo, is described as new.

The pseudoscorpion fauna of Florida is much richer, more diverse, and
more interesting than the published literature would lead one to suppose.
While nearly 30 species have been recorded from the state, an equal number or
more await listing or description. From several sources, chiefly the Florida
State Collection of Arthropods, I have accumulated a number of new and
little known forms which deserve to be recognized. This, then, is the first in a
series of papers dealing with the pseudoscorpions of Florida.
Inasmuch as the genus Aldabrinus Chamberlin (1930) has been known
from only a single specimen from the Aldabra Islands in the Indian Ocean, it
was with considerable surprise that 3 specimens pertaining to the genus were
noted in 2 collections from Key Largo, Monroe County, Florida. Because of
the unusual nature of this discovery, I have reexamined the type specimen of
Aldabrinus aldabrinus Chamberlin and compared it directly with the new
specimens. I also take this opportunity to redescribe the type of A. aldabrinus
as the basis for a more complete diagnosis of the genus.

Family Olpiidae Chamberlin
Subfamily Garypininae Daday
Genus Aldabrinus Chamberlin

Aldabrinus Chamberlin, 1930, p. 589 and 597.
Diagnosis emendedd): Diplosphyronid pseudoscorpions with the
characteristics of the family Olpiidae, subfamily Garypininae, namely: tarsi of
all legs divided; chelicera with inner margin of movable finger not dentate but
having a single subapical lobe at distal end; plates of serrula interior fused
basally to form a velum; laminal seta present; chela with venom apparatus
well developed in both fingers; pleural membranes smoothly, longitudinally
plicate; coxal area not widened posteriorly; arolia of pedal tarsi longer than
claws and divided. And with the following particular characters: carapace

'Contribution No. 291, Bureau of Entomology, Division of Plant Industry, Florida Department
of Agriculture and Consumer Services, Gainesville, Florida 32602.
2Research Associate, Florida State Collection of Arthropods, Florida Department of Agriculture
and Consumer Services, Gainesville.

The Florida Entomologist

with only anterior four-fifths or so strongly sclerotized, and with shallow, but
distinct, transverse furrow; 4 well developed eyes; abdomen long and narrow;
some tergites divided or nearly so; 2 discal setae on sternites 6-8 in addition to
marginal setae; cheliceral hand with 4 long setae, laminal seta located much
posterior to interior seta; flagellum of 4 setae, 1 or more denticulate distally;
movable finger with tip slightly furcate; no lamina exterior present; palps
heavy, especially chela, depth of hand equal to its length; movable chelal
finger with 2 trichobothria, fixed finger with 7; femur with or without a fine
trichobothrium on dorsum; leg I with telofemur much longer than basifemur,
the joint between the 2 apparently immovable; leg IV with short tactile seta at
middle of metatarsus; subterminal tarsal setae long, simple.
Remarks: Aldabrinus is closely related to Paraldabrinus Beier (1966)
which is represented by a single species, P. novaecaledoniae, from New
Caledonia in the Pacific Ocean. From that genus Aldabrinus is easily distin-
guished by the possession of 2 trichobothria on the movable chelal finger,
rather than 1. It is also close to Nelsoninus Beier (1967) from New Zealand,
from which it differs in the heavier palpal chela, presence of only 4 setae on the
cheliceral hand, and shorter tactile seta on metatarsus IV.

A ldabrinus aldabrinus Chamberlin
Fig. 1-5
Aldabrinus aldabrinus Chamberlin, 1930, p. 597.
While the description by Chamberlin is adequate to define the species,

Fig. 1-5. Aldabrinus aldabrinus Chamberlin, holotype female.
1-Cheliceral flagellum. 2-End of movable finger of chelicera. 3-Lateral view
of left chela. 4-Leg I. 5-Leg IV.

Vol. 57, No. 1

Muchmore: Pseudoscorpions from Florida

there are several additional features which deserve recognition. Therefore, the
holotype female (JC 507.01001), from "Il Esprit, Aldabra Islands, December,
1908," borrowed from the British Museum (Natural History) is redescribed
below. The specimen is somewhat damaged, especially the right chela which is
Description of female: Carapace longer than broad; anterior five-sixths
heavily sclerotized and irregularly convex posteriorly; surface smooth and
with a shallow but distinct transverse furrow 0.62 length of carapace from
anterior margin; 4 weakly corneate eyes, anterior pair slightly larger than
posterior; carapacial chaetotaxy 4-4-2-4-4-5=23. Coxal chaetotaxy 1-
m-7-2:3(4)-1:4-2:2-1:3-1; the small seta (m) on medial edge of palpal coxa is
sharply bent near base.
Abdomen very long. Some posterior tergites and sternites divided, but the
sclerites are too thin and indistinct to permit an accurate determination;
surfaces smooth; pleural membranes longitudinally smoothly striate. Tergal
chaetotaxy 4:4:5:6:6:6:6:6:6:T2T2T2T:TT:2. Sternal chaetotaxy
8:(1)4(1):(2)4(2):5: 2. 22 :6:T2T2T2T:T1TT1T:2.
Chelicera 0.38 as long as carapace. Hand with 4 setae, all very long; laminal
seta much posterior of interior seta. Flagellum of 4 setae, distal 1 broad and
serrate along margin, others subterminally denticulate (Fig. 1). Fixed finger
with 1 or 2 small and 3 medium sized teeth; no lamina exterior present.
Movable finger with tip furcate and with prominent lateral subapical lobe
(Fig. 2); galea long, slender, with 3 small, curved, terminal rami; serrula
exterior with 15 blades.
Palps rather heavy; surfaces smooth. Proportions of segments similar to
those of A. floridanus, as shown in Fig. 10; trochanter 1.95, femur 2.4, tibia 2.0,
and chela (without pedicel) more than 2.5 times as long as broad; depth of
hand equal to length; movable finger 1.12 times as long as hand. Fingers of
chela heavy and strongly curved toward internal side at tips. Dorsum of femur
apparently without a trichobothrium setaee broken). Movable chelal finger
with only 2 trichobothria and fixed finger with 7, as shown in Fig. 3; movable
finger also with 5 spinelike setae regularly spaced along finger just internal to
dental row, and fixed finger with 1 such seta on internal surface near distal
end. Movable finger with row of 34 or 35 contiguous, retroconical teeth, all
with cusps, and fixed finger with 34-36 similar teeth; each finger with a large
terminal venedens, but venom ducts not apparent.
Legs short and robust; leg I with telofemur much longer than basifemur,
the joint between the 2 apparently immovable (Fig. 4); Leg IV with femur 2.4
and tibia 2.4 times as long as deep, and telotarsus little longer than metatarsus
(Fig. 5); metatarsus with a weak tactile seta at middle of outer margin.
Subterminal tarsal setae long, simple. Arolia divided, twice as long as claws,
which are heavy, strongly curved.
Male: Unknown.
Measurements (mm): Body length 3.55; abdominal breadth 0.96. Carapace
length 0.66; greatest breadth 0.50. Chelicera 0.25 by 0.14. Palpal trochanter
0.33 by 0.17; femur 0.445 by 0.185; tibia 0.435 by 0.22; chela (without pedicel)
0.805 long (breadth indeterminable); hand (without pedicel) 0.41 by 0.41;
movable finger 0.46 long. Leg I: basifemur 0.105 by 0.11; telofemur 0.18 by
0.125; tibia 0.17 by 0.095; metatarsus 0.075 by 0.06; telotarsus 0.08 by 0.06. Leg

The Florida Entomologist

IV: entire femur 0.48 long; basifemur 0.16 by 0.12; telofemur 0.43 by 0.20; tibia
0.30 by 0.125; metatarsus 0.09 by 0.08; telotarsus 0.11 by 0.075.

Aldabrinus floridanus, new species
Fig. 6-12
Material: Holotype female (WM 3100.01001) taken "beating vegetation in
tropical hammock" on north Key Largo, Monroe County, Florida, 30
December 1966 (Camilla B. Weems). Paratype male and female also from Key
Largo, 7 December 1966 (R. E. Woodruff). The types are in the Florida State
Collection of Arthropods, Gainesville.
Diagnosis: Quite similar to Aldabrinus aldabrinus, but generally slightly
smaller and palpal chela considerably smaller; carapace with only 18-20 ves-
titural setae; basal teeth of both chelal fingers without cusps; and palpal
femur with small, but definite, trichobothrium near center of dorsum.
Description of female: (Figures are given for holotype, sometimes followed
in parentheses by those for paratype.) Carapace and palps dark, smoky brown,
other sclerotized parts light brown. Carapace distinctly longer than broad;
anterior four-fifths heavily sclerotized and irregularly convex posteriorly;
surface smooth and with a shallow, but distinct, transverse furrow 0.63 length
of carapace from anterior margin; 4 well developed eyes, anterior pair slightly
larger than posterior; carapacial chaetotaxy 4-2-2-4-4-2 = 18 (paratype with
additional setae near posterior end, and a total of 20). Coxal chaetotaxy
1-m-6-2:4-1:4-1:2-1:2-1; the small seta (m) on medial edge of palpal coxa is
sharply bent near base.
Abdomen very long, abruptly broader and higher than carapace (Fig. 6).
Tergite 1 divided, 2-4 entire, and 5-9 partly divided; sternites 5-9 divided;
surfaces smooth; pleural membranes smoothly, longitudinally striate. Tergal
chaetotaxy 3:4:4:4:4:4:5:6:6:T2T2T2T:TT:2 (paratype with 6:4:5:4:4:4:-).
Sternal chaetotaxy 8:(2)5(2):(2)2(2):4::2:. :6:T2T2T2T:T1TT1T:2, as
shown in Fig. 7 (paratype with 6, rather than 4, marginal setae on sternites
5-8). Internal genitalia with 1 large, median and 2 small, lateral cribriform
plates (Fig. 8).

Chelicera about one-third as long as carapace; hand with 4 setae, all very
long, laminal seta much posterior to interior seta; flagellum of 4 setae, all more
or less denticulate distally, the second one longest (Fig. 9). Fixed finger
without a lamina exterior; internal margin with 2 small and 3 or 4 medium
sized teeth. Movable finger with tip furcate and with prominent lateral
subapical lobe and one small rounded denticle (Fig. 10); galea long, slender,
with 3 small, curved, terminal rami; serrula exterior with about 15 blades.
Palps rather heavy; surfaces.smooth. Proportions of segments shown in
Fig. 11; trochanter 1.8(1.65); femur 2.35(2.6); tibia 1.95(1.95) and chela
(without pedicel) 2.25(2.05) times as long as broad; hand (without pedicel)
1.0(1.0) times as long as deep; movable finger 1.03(1.08) times as long as hand.
Fingers of chela heavy and strongly curved toward internal side at tips.
Dorsum of femur with a fine trichobothrium near the middle. Movable chelal
finger with only 2 trichobothria and fixed finger with 7, as shown in Fig. 12;
movable finger also with 5 spinelike setae regularly spaced along finger just
internal to dental row, and fixed finger with 1 such seta on internal surface
near distal end. Movable finger with 32 (35) contiguous, retroconical teeth and

Vol. 57, No. I

Muchmore: Pseudoscorpions from Florida

C -'

Fig. 6-12. Aldabrinus floridanus, new species. 6-Lateral view of body.
7-Ventral view of abdomen of holotype female. 8-Cribriform plates of para-
type female. 9-Cheliceral flagellum. 10-End of movable finger of chelicera.
11-Dorsal view of left palp of holotype female. 12-Lateral view of right chela
of holotype female.

6 The Florida Entomologist Vol. 57, No. 1

fixed finger with 30 (33) similar teeth; basal 6-8 teeth on movable finger and
basal 5-6 teeth on fixed finger rounded, lacking cusps; each finger with a large,
terminal venedens, but venom ducts not apparent because of density and
curvature of fingers.
Legs short and robust; leg I with telofemur much longer than basifemur,
the joint between the 2 apparently immovable; leg IV with femur 2.4(2.6) and
tibia 2.35(2.35) times as long as deep, and telotarsus little longer than meta-
tarsus; metatarsus with weak tactile seta at middle of outer margin. Subter-
minal tarsal setae long, simple. Arolia divided, twice as long as claws, which
are heavy, strongly curved.
Male: Essentially like female but slightly smaller and less robust, and
darker in color. Palpal trochanter 1.75, femur 2.7, tibia 2.2 and chela (without
pedicel) 2.3 times as long as broad; hand (without pedicel) 1.1 times as long as
deep; movable finger 1.02 times as long as hand. Carapace with 18 vestitural
setae, including 3 at anterior and 2 at posterior margin. Cheliceral hand with 4
setae; flagellum of 4 setae, all denticulate subterminally except basal short 1.
Chaetotaxy of anterior sternites 8:[2-2]:(1)6(2):(2)1(2):4: 2:2::-(others
broken); pattern of setae on genital opercula identical to that in female but
with addition of 2 pair of small setae on anterior face of posterior operculum.
Internal genitalia not studied in detail, but without any obviously unusual
Measurements (mm): First figures given are for the holotype female,
followed by those of the male paratype in parentheses, then by those of the
female paratype. Body length 3.07(?)?; abdominal breadth 0.89(?)?. Carapace
length 0.59(0.58)0.635, greatest breadth 0.41(0.43)0.445. Chelicera
0.20(0.20)0.22 long. Palpal trochanter 0.28(0.265)0.30 by 0.155(0.15)0.18; femur
0.40(0.435)0.49 by 0.17 (0.16)0.19; tibia 0.36(0.41)0.43 by 0.185(0.185)0.22; chela
(without medical) 0.65(0.615)0.68 by 0.29(0.265)0.33; hand 0.33(0.325)0.34 by
0.33(0.30)0.35; movable finger 0.34(0.325)0.385 long. Leg I of holotype;
basifemur 0.095 by 0.095; telofemur 0.16 by 0.11; tibia 0.155 by 0.08; metatar-
sus 0.065 by 0.06; telotarsus 0.095 by 0.055. Leg IV of holotype: entire femur
0.435 long; basifemur 0.15 by 0.095; telofemur 0.385 by 0.18; tibia 0.26 by 0.11;
metatarsus 0.08 by 0.075; telotarsus 0.105 by 0.065.
Etymology: The species is named floridanus for the state of Florida, where
it lives.
Remarks: The occurrence of representatives of Aldabrinus in America as
well as the Malagasy Region suggests the possibility that this genus, like
Solinus, is presently circumtropical in distribution, though, alternatively, the
2 species may only be isolated remnants of a former widespread distribution. A
further possibility is, as Dr. H. V. Weems, Jr. has pointed out (in litt.), that
Aldabrinus floridanus is an exotic introduction from some other part of the
world, brought in either in ships' ballast or with plant material. Much further
collection and study will be necessary before this problem can be solved.


I wish to thank K. H. Hyatt of the British Museum (Natural History) for
the loan of the type of A. aldabrinus and H. V. Weems, Jr. for the opportunity
to examine the Florida material. The assistance of Charlotte H. Alteri in

Muchmore: Pseudoscorpions from Florida 7

preparing the illustrations is gratefully acknowledged. This work was sup-
ported in part by Grant GB 37570 from the National Science Foundation.


Beier, M. 1966. Ergebnisse der osterreichischen Neukaledonian-Expedition
1965. Pseudoscorpionidea. Ann. Naturhistor. Mus. Wien 69:363-371.
Beier, M. 1967. Contributions to the knowledge of the Pseudoscorpionidea
from New Zealand. Rec. Dominion Mus. 5:277-303.
Chamberlin, J. C. 1930. A synoptic classification of the false scorpions or
chela-spinners, with a report on a cosmopolitan collection of the same.
Part II. The Diplosphyronida (Arachnida, Chelonethida). Ann. Mag.
Nat. Hist., ser. 10, 5:1-48, 585-620.


Beginning with this issue, The Florida Entomologist will publish short
notes, notices, and abstracts. These items will appear in scattered spaces
throughout and at the end of each issue. We are soliciting notes which present
in 250-400 words, new records, ideas, observations, etc. of an entomological
nature. We will also publish preview abstracts of work that is being completed
but is not yet ready for publication in its completed form (abstracts). In
addition, 2 other classes of information will be published as space permits: the
editor will select prepublished abstracts of articles of potential interest to
society members, that appear in journals that are less apt to be checked by
entomologists (prepublished abstracts). The editor will write abstracts for
articles of interest that are not already abstracted (notices). The classification
of each item will be indicated.
Dr. James E. Lloyd (Department of Entomology, University of Florida,
Gainesville) will edit these items. Please note examples on p. 22, 32, 38, 46, 90,
and 96.



Department of Entomology and Nematology
University of Florida, Gainesville 32611


Five species of Gryllus occur in southeastern United States: assimilis
(Fabricius), firmus Scudder, fultoni (Alexander), ovisopis Walker, and rubens
Scudder. They can be identified by head and tegminal color patterns, tooth
number and length of stridulatory file, and dimensions and proportions of
wings, pronotum, ovipositor, posterior femur, and tympana.

From 1915 to 1957, all field crickets of eastern United States were assigned
to a single species: Gryllus (or Acheta) assimilis. Prior to 1915, as many as 12
species were recognized, and these were separated on the basis of coloration,
size, wing venation, and lengths of structures such as tegmina, legs, and
ovipositor. These characters are variable, and after making careful
measurements and comparisons of hundreds of preserved specimens, Lutz
(1908) and Rehn and Hebard (1915) concluded that all field crickets in North
America belonged to a single though highly variable species.
Fulton (1952) proved that this approach oversimplified Gryllus taxonomy.
He showed that in North Carolina four populations occurred with distinctive
songs, seasonal histories, and habitats. In crossing experiments he got no
hybrids between populations, although his control crosses usually produced
offspring. Alexander (1957) revised the taxonomy of Gryllus of eastern United
States, recognizing 5 previously described species and 1 new species. Alexander
and Walker (1962) added G. assimilis (strict sense) to the Gryllus known from
southeastern United States, and Walker (1974) added G. ovisopis.
This paper presents a key for identifying adult field crickets of southeast-
ern United States. No adequate key has been published, and one is needed.
For example, in the Florida fire ant project, Mirex bait residues are being
monitored with field crickets (D. J. Wojcik, pers. comm.), and for effective
monitoring, the species must be distinguished.
The key is intended to be useful in identifying dried specimens or specimens
preserved in alcohol. Tegminal characters are more easily seen if the tegmen is
mounted between glass slides, a simple procedure with alcohol-preserved
specimens. The key is most effective in identifying mature adults, since general
specimens lack the characteristic markings used in the key. Measurements
were made with the apparatus described by Grant (1965).
File Characters. Rakshpal (1960) and Alexander and Walker (1962)
reported that the number of teeth in the stridulatory file is useful in distin-

'Florida Agricultural Experiment Station Journal Series No. 5008.
'Research Associate, Florida State Collection of Arthropods.

Nickle and Walker: Key to S.E. Field Crickets

guishing certain species of Gryllus. Table 1 and Fig. 10 show the results of
examining files of the 5 species considered here. The greater number of teeth
distinguishes G. firmus. G. ovisopis and G. fultoni overlap in each of their file
characteristics (Table 1), but their clusters of points are discrete (Fig. 10). G.


Number of Teeth Length of File (mm) Teeth per mm
i + S.D. range i + S.D. range i + S.D. range

assimilis* 113+5 102-121 3.2+0.2 2.6-3.5 36+2 33-39
firmus** 185+ 13 166-210 3.8+0.3 3.3-4.4 48+3 42-53
fultoni** 115+8 100-133 2.8+0.2 2.2-3.1 41+2 37-46
ovisopis** 141+8 126-154 2.7+0.7 2.3-3.1 50+4 45-59
rubens** 103+7 91-117 2.7+0.2 2.3-3.2 40+2 34-42.

*Homestead, Fla.
**Alachua Co., Florida

rubens, G. assimilis, and G. fultoni broadly overlap in the features of their
Geographical Ranges. Gryllus assimilis is restricted to south Florida
below Lake Okeechobee. G. rubens and G. firmus are widely distributed in the
southern states and have been found in all parts of Florida. The range of G.
ovisopis is poorly known, but it has not been found south of Gainesville.
Northward it probably extends at least into south Georgia. G. fultoni is widely
distributed in the eastern United States, but in Florida it is not known south of
Gainesville except for a population on Key Largo!
The western limits of usefulness for the key are uncertain. In western
Florida and Mississippi, G. rubens is replaced by, or is overlapped by, or
intergrades with, a similar but faster trilling species known as G. integer
Scudder (Alexander 1968).


1. Lateral arms of ecdysial suture well-defined. Most of cir-
cumocular area light yellow-brown (Fig. 1). Metathoracic
wings never shorter than tegmina (i.e. macropterous). Occur-
ring only in South Florida ..- ......- Gryllus assimilis (Fabricius)
1'. Lateral arms of ecdysial suture poorly defined or obso-
lete. Most of circumocular area dark brown or with only a
small patch of light beneath eye (Fig. 2, 3). Metathoracic
wings sometimes shorter than tegmina (i.e. macropterous or
micropterous). Not restricted to south Florida ...........................- 2

The Florida Entomologist

36 t7

Fig. 1-9. Morphological features of Gryllus species. 1-3. Head color pat-
terns, dorsolateral view: 1-assimilis; 2-firmus, rubens; 3. ovisopis, fultoni.
4-7. Right tegmina of males: 4-o'isopis; 5-firmus; 6-rubens; 7-fultoni.
8-Tympanal measurements. 9-Pronotal measurements.

2(1'). Length of tegmina less than 2 times median length of pro-
notum .----.. --.. .. .. .--- 3
notum ...~..........................................................~....~...... 3

Vol. 57, No. 1

Nickle and Walker: Key to S.E. Field Crickets 11

190 A assimilis
firmus **
o fultoni *
180 a ovisopis ,
o rubens

150 A



120 OA o o
0oO A
110 0 000 A
O O 0

100 0 o 0 o 0
90 0

2.0 2.2 2.4 2.6 2.8 3.0 3.2 3.4 3.6 3.8 4.0 4.2 4.4
length of file (mm)

Fig. 10. Scatter diagram showing characteristics of the stridulatory files of
5 species of Gryllus.

2'. Length of tegmina greater than 2 times median length of
pron otu m ..--------.- -- --..- .-- --. --.------- .................... ..... ..... ...... 4
3(2). Tegmina dark brown (Fig. 4). Stridulatory file usually with
more than 125 teeth and mean number of teeth x mm-'
greater than 45. Length of ovipositor greater than x 1.30
length posterior femur. Adults only in fall ......--------..... ...........
...... -- ----------........ ..... .......... .. Gryllus ovisopis W walker
3'. Tegmina pigmented as in Fig. 7. Stridulatory file with
fewer than 125 teeth and mean number of teeth x mm-'
less than 45. Length of ovipositor less than x 1.20 length
posterior femur. Adults not restricted to fall ...........................
------........... -----.......... Gryllus fultoni (Alexander) (in part)
4(2'). Stridulatory file with more than 160 teeth. Lateral fields
of tegmina with numerous conspicuous cross-veins. Colora-
tion of costal area entirely dark brown with light-colored
veins and cross-veins (Fig. 5) ......... .............. Gryllus firmus Scudder

12 The Florida Entomologist Vol. 57, No. 1

4'. Stridulatory file with fewer than 160 teeth. Lateral fields
of tegmina with few or inconspicuous cross-veins. Coloration
of costal area usually light brown and venation not con-
trastingly lighter -- ---......... ....------ -- ........................... ...... 5
5(4'). Lateral field of tegmen with a well-defined narrow dark
stripe along costal vein (Fig. 6). Length of posterior tym-
panum less than x 3.5 length of anterior tympanum. Pro-
notal width more than x 1.3 pronotal length .....--..---..............
.------------ ................ .. ......... .. Gryllus rubens Scudder
5'. Lateral field of tegmen lacking a well-defined stripe along
costal vein (Fig. 7). Length of posterior tympanum greater
than x 3.5 length of anterior tympanum. Pronotal width
less than x 1.3 pronotal length ....... ...............
----- -- -----................ Gryllus fultoni (Alexander) (in part)


Alexander, R. D. 1957. The taxonomy of the field crickets of the eastern
United States (Orthoptera: Gryllidae: Acheta). Ann. Ent. Soc. Amer.

Alexander, R. D. 1968. Life cycle origins, speciation, and related phenomena in
crickets. Quart. Rev. Biol. 43:1-41.

Alexander, R. D., and T. J. Walker. 1962. Two introduced field crickets new to
eastern United States (Orthoptera: Gryllidae). Ann. Ent. Soc. Amer.

Fulton, B. B. 1952. Speciation in the field cricket. Evolution 6:283-295.

Grant, H. J., Jr. 1965. A measuring device for use in insect systematics. Ent.
News 76:249-251.

Lutz, F. E. 1908. The variation and correlations of certain taxonomic
characters of Gryllus. Univ. of Chicago, Chicago. 63 p.

Rakshpal, R. 1960. Sound-producing organs and mechanisms of sound
production in field crickets of the genus Acheta Fabricius (Orthoptera:
Gryllidae). Can. J. Zool. 38:499-507.

Rehn, J. A. G., and M. Hebard. 1915. The genus Gryllus as found in America.
Proc. Acad. Nat. Sci. Phila. 67:293-322.

Walker, T. J. 1974. Gryllus ovisopis n. sp.: an egg-diapausing univoltine
cricket with no calling song (Orthoptera: Gryllidae). Fla. Ent. 56:13-22.



Department of Entomology and Nematology
University of Florida, Gainesville 32611

G. ovisopis, common in north Florida woods, is the first Gryllus known to
lack a calling song. Its courtship song is similar to that of other Gryllus, but its
aggressive song is dominated by frequencies of 12-16 kHz rather than 4-5 kHz.
Indoor and outdoor rearing experiments and periodic collecting showed
ovisopis to be strictly univoltine with all individuals becoming adult in Sep-
tember and early October. Similar studies indicated that G: fultoni (Alex-
ander), a close relative, has both univoltine and bivoltine cycles; and even
within one week's progeny of a single female, individuals may become adult
over a period of seven months. Attempts to hybridize ovisopis and fultoni
failed. Seasonal rather than geographical isolation may have initiated specia-
tion in the ancestral population that became ovisopis and fultoni.

Rehn and Hebard's (1915) conclusion that U. S. Gryllus represented a
single species was generally accepted until Fulton (1952) published convincing
evidence that 4 species occurred in North Carolina. Alexander (1957), unlike
Fulton, used binominal nomenclature for Gryllus species in eastern United
States, recognizing 4 previously described species and describing a fifth species
as Gryllus fultoni. Subsequently Alexander and Bigelow (1960) described G.
veletis, and Alexander and Walker (1962) reported the occurrence of G. as-
similis (Fabricius) in Florida.
This paper describes a previously unrecognized species of Gryllus from
eastern United States. G. ovisopis is the only Gryllus known to lack a calling
song. It is the only southeastern Gryllus that is strictly univoltine. Unlike
fultoni, a species with which it was confused, it diapauses in the egg stage, and
the name ovisopis (ovi-, egg; sopis, sleep) refers to this characteristic.
Morphologically ovisopis can be distinguished from other eastern Gryllus by
its short tegmina, long ovipositor, and closely-spaced file teeth (Nickle and
Walker 1974).

Gryllus ovisopis, n. sp.
Taciturn Woods Cricket
Holotype.-Male, FLORIDA: Alachua Co., NW 1/4, Sec. 31, T9S, R19E,
collected as juvenile, 7 June 1972, in deep leaf litter in mesic hammock, reared

'Orthoptera: Gryllidae.
'Florida Agricultural Experiment Station Journal Series No. 5059. This study was aided by NSF
Grant GB 20749. I thank Dr. J. J. Whitesell for aid in the field and review of the manuscript, Mr. D.
L. Mays for living specimens from several locations in north Florida, and Dr. J. E. Lloyd for help with
the manuscript.
'Research Associate, Florida State Collection of Arthropods.

The Florida Entomologist

outdoors, adult 10 Sept. 1972, T. J. Walker; deposited in (U. S.) National
Museum of Natural History. Black except for lighter areas on proximal por-
tions of femora and costal margins of tegmina. Length of body, 26 mm;
pronotal length x width, 5.6 x 7.5; length of tegmen, 10.0; length of hind
femur, 16.2. Length of wings less than half length of tegmina. Stridulatory file
3.13 mm with 147 teeth.
Allotype.-Female, same locality as holotype, 15 Oct. 1967, T. J. Walker;
deposited in (U. S.) National Museum of Natural History. Similar to holotype.
Length of body, 28 mm; pronotal length x width, 6.3 x 7.9; length of tegmen,
11.0; length of hind femur, 16.6; length of ovipositor, 23.
Paratypes.-41 males, 50 females, Florida State Collection of Arthropods.
FLORIDA: Alachua Co., 5 females, collected as adults at 5 sites near Gaines-
ville, 10 Oct. 1971, J. J. Whitesell and D. L. Mays, 12 Oct. 1971, J. J. Whitesell,
20 Oct. 1971, D. Baker, 6 Nov. 1971, T. J. Walker, 20 Oct. 1972, J. E. Lloyd; 34
males, 38 females, reared from juveniles or from eggs laid by females collected
at 4 sites near Gainesville, 1967, 1971, 1972, T. J. Walker and J. J. Whitesell.
Baker Co., 1 male, 1 female, reared from juveniles collected 1 mi. s. Georgia
line, Fla. 121, 18 Aug. 1970, D. L. Mays. Leon Co., 5 males, 2 females, reared
from juveniles collected Tall Timbers Research Station, 2 July 1970, D. L.
Mays. Wakulla Co., 1 female, Ochlockonee River State Park, 3 Oct. 1970, D. L.
Mays; 1 male, 3 females, progeny of above female.

G. ovisopis occurs in the broadleaf forests known as mesic hammock and
xeric hammock (Laessle 1942) and in late secondary successional stages lead-
ing to these. It occurs on and in leaf litter and under objects such as logs and
discarded pieces of plywood. When confined in jars partially filled with sand,
larger juveniles and adults sometimes conceal themselves, as do other Gryllus
spp., in shallow burrows. G. ovisopis often occurs with G. fultoni; however,
fultoni sites include wetter and drier, more-often-burned woods. G. ovisopis is
most abundant at sites that are buffered from extremes of moisture and have
deep leaf litter.
I long confused ovisopis with fultoni because they often occurred together
and ovisopis had no identifying calling song. Their distinctness became ap-
parent during studies of seasonal life histories (Fig. 1). These studies included
systematic field observations of adults and laboratory and field rearing of
progeny of field-collected, field-fertilized females. In 1970-71 such females
were individually confined in screen-capped gallon jars with substrate for
oviposition (800 ml moistened sterilized sand), food (Purina dog chow in a vial
cap), and water (15-dram vial with a stopper penetrated by a dental cotton
wick). The jars were kept on the ground in a wooded area. A sheet of plywood
supported by 4 posts protected the jars from rain and direct sun but allowed
natural photoperiod; temperatures were within the range encountered at
ground level elsewhere in the woods. Each week the females were transferred
to new jars. The jars with 1-week's oviposition were alternately left under the
shelter in the woods or transferred to a rearing room held at 25 + 3C and a
photoperiod of 16 L: 8 D.
The jars in the laboratory and in the woods were tended weekly and the
crickets censused. Four weeks after initial hatch, all juveniles were transferred
from the oviposition jar to a new gallon jar similarly equipped with sand, food,

.Vol. 57, No. 1

Walker: Gryllus ovisopus, n.sp.


MID U. JUV./ ..
ADULTS -------

SI I 111111111 I II

Fig. 1. Seasonal life cycles of G. ovisopis and G. fultoni at Gainesville,
Florida, largely based on periodic collection of individuals and subsequent
outdoor rearing of juveniles and of the progeny of adult females. The oc-
currence of adults of fultoni is based on records of calling males except that the
dotted line indicates a period when no calling songs were heard but when
outdoor rearing records suggested adults were present.

and water. A 13 X 5-cm cylinder (ht X diam) made of a 13 x 18-cm card was
added to the juvenile jars to increase the standing room. The oviposition jar
was watched for further hatch for several weeks. If none occurred, first a
sample and then the entire 800 ml of sand was examined for unhatched, viable
eggs by a washing technique. As F, adults appeared, they were removed weekly
from the juvenile jars and preserved for morphological studies.
Females that eventually proved to be fultoni (n = 7), were collected in the
spring and laid eggs that hatched in 3 to 7 weeks indoors or out. The juveniles
of fultoni in a single jar often had 2 modes of development: some developed
rapidly and became adults in late summer or fall; others stopped developing in
the middle instars, and did not resume development for a month or more in the
laboratory or until the following spring outdoors. Some that matured out-
doors in late summer and fall were transferred to new jars outdoors with the
aim of monitoring the development of their offspring. Eggs were obtained from
early September through November. Those laid in September hatched in
about 4 weeks and produced early mid-stage juveniles by December. These
individuals (F,) did not survive, but slightly larger fultoni juveniles (F,) in
other jars survived and produced adults the following spring. Most eggs laid in
October and November hatched in 5 to 7 weeks and died as early-stage
juveniles the following spring. In 1 jar with eggs laid 9.Oct.-27 Nov., 40 hatched
between 27 Nov. and 26 Dec. These died by 5 Mar. Two additional hatchlings
were found on 30 Apr., and these died by 14 May. If only the above data are

The Florida Entomologist

considered, one would have to conclude that fultoni adults maturing in late
summer and early fall contribute nothing to future gene pools. However,
many uncaged fultoni mature during this period as evidenced by a resurgence
of male calling activity during August and September (Fig. 1). Calling then
ceases until mid December, although adults should occur on the basis of
outdoor rearing data. Perhaps the most reasonable hypothesis compatible
with the present data is that adults maturing in late summer and early fall lay
eggs that soon hatch and sometimes contribute to the adult population of the
following spring. Those maturing later in the fall (if such occur outside of jars)
do not begin mating and egg laying until winter, at which time the likelihood
of the hatchlings surviving is improved. One further hypothesis: the oc-
currence of 2 April hatchlings from Oct.-Nov. eggs suggests that variation
exists in fultoni eggs that, if selected for, could lead to an ovisopis-type life
cycle (Fig. 1).
Females that eventually proved to be ovisopis (n= 4) were collected in
October and November. They were morphologically distinct from those
collected in the spring and laid eggs that required 10-16 weeks to hatch at 25 +
3C and 20-30 weeks to hatch outdoors. Juveniles in a single jar, whether kept
indoors or out, were nearly synchronous in their development. In the labora-
tory (25 3C, 16 L: 8 D) development time from egg laying to eclosion of the
adult varied from 34-41 weeks (n = 13). In the jars in the woods, all last instars
molted to adults (n = 17) within a 4-week period (Table 1, first line).

JARS, 17 OCT. 1971 TO 4 OCT. 1972.

Date of final molt of Range of dates
Origins of individuals n median individual* of final molts

Eggs laid 17 Oct.-6 Dec. 7 10 20 Sept. 20 Sept. 4
1971 by 2 females
collected from sep-
arate demes

Juveniles collected 17 7 14 Sept. 20 Sept. 4
from 3 demes 25 Apr.-
27 July 1972

Juveniles collected 7 6 14 Sept. 28 Sept. 3
from 2 demes 14 Aug.-
25 Sept. 1972

TOTAL 31 23 14 Sept. 20 Sept. 5

*Since jars were censused weekly, the best estimate of median date of molt is 3 1/2 days prior to the
census date of the median adult of the appropriate sex. Adults found on a particular census date
might have molted at any time during a 7-day period. It is assumed that the first final molt
occurred 3 1/2 days prior to its census date and that the last final molt did likewise.

Vol. 57, No. 1

Walker: Gryllus ovisopus, n.sp.

In 1972 the life histories studies were expanded to compare speed of
development in wild crickets with those confined outdoors with a surfeit of
food and water. Woods crickets of all stages that could be found were collected
at biweekly to triweekly intervals in 3 areas several miles apart, and the
juveniles were allowed to mature outdoors in sheltered gallon jars. The
crickets in the jars apparently developed at the same rate as those loose in the
woods: the field-collected juveniles continued to match in size and stage of
development those being reared in the jars outdoors. Juveniles collected in
late August and September matured within a few days of those collected
earlier as juveniles or reared from eggs laid in jars the previous year (Table 1).
No wild adults were seen while searching 4 Sept., but 3 males were caught 24
All available evidence indicates that ovisopis is strictly univoltine with an
obligatory egg diapause. A higher degree of synchronism of final molts out-
doors than in laboratory rearing suggests that an environmental cue such as
photoperiod may be involved in timing some phase of juvenile development. In
contrast to ovisopis, fultoni at Gainesville shows no egg diapause and has a
partial second generation each year. It calls, and presumably mates, at all
times of the year except when ovisopis is mating (Fig. 1).

Most biologists agree that the ultimate criterion of species status for a
population of sexually reproducing animals is that no significant genetic
exchange occurs under natural conditions between it and other such popula-
tions. For populations that occur together this is a practical criterion.
Populations of G. ovisopis occur intermingled with those of G. fultoni and
to a lesser but noteworthy extent with those of G. rubens Scudder and G.
firmus Scudder. I have found no individuals intermediate in morphological
characters (Nickle and Walker 1974) between ovisopis and any of the 3 other
Gryllus species living with it and consequently consider it a species.

AND G. fultoni.

Number of Replicates

X Producing Producing

Total eggs progeny

ovisopis X ovisopis 4 4 4
ovisopis X fultoni* 2 2 0
fultoni X ovisopis** 4 3 0
fultoni X fultoni 4 4 4

*The female in 1 replicate was taken out of the hybridization experiment after 6 weeks and placed
with a fultoni male. Eggs laid during the first 6 weeks did not hatch; subsequent ones produced
normal fultoni progeny.
*Transfer of spermatophores with no abnormal delay observed in 2 replicates.

The Florida Entomologist

The experimental crosses described below were not designed to test the
specific status of ovisopis as much as to produce hybrids between a Gryllus
with a calling song and one without. The closest relative of ovisopis is proba-
bly fultoni (see below), but their mating seasons barely overlap outdoors. By
rearing ovisopis and fultoni in the laboratory, I obtained virgin adults of both
species at the same time. Pairs of crickets were held at 25 + 30C and 16 L: 8 D
in gallon jars equipped and tended weekly as described above under seasonal
life cycles. Each of the 4 possible crossings was made a minimum of 2 times.
Results are shown in Table 2. Interspecific matings occurred and 13 of 14
females laid eggs; however, only conspecific pairs produced offspring.
These results agree with previous studies of interfertility of Gryllus spp.
(Alexander 1968). Many species will hybridize, but so far no egg-diapausing
species has been successfully crossed with a juvenile-diapausing species.

The most peculiar feature of ovisopis is its lack of a calling song. Males of
other Gryllus (including 5 Florida species) are easily recognized in the field by
their persistent, distinctive calling songs. The absence of such a song in
ovisopis was responsible for my not recognizing this species earlier.
Several sets of evidence support the contention that ovisopis has no calling
song. The first is that in 15 years of field studies of north Florida cricket calls
I have failed to detect one. During this period I lived within 50 ft. of popula-
tions of ovisopis. For more than 2 years I made weekly censuses of all calling
crickets in 2 habitats that had vigorous populations of ovisopis. Yet I have
detected ovisopis only 3 times in the field by its sound: twice by courtship and
once by aggressive sounds. Another set of evidence is that in more than 2 years
of laboratory rearing of ovisopis I never heard a calling song. A third set is that
I kept 15 individually caged adult males in my bedroom for 1-3 weeks and
never heard a song. In similar tests with other Gryllus, 12 or more of the 15
individuals called within the first week.
The possibility that ovisopis produces an ultrasonic calling song can be
discounted for these reasons: (1) the frequencies produced during courtship
and fighting are similar to the frequencies in the acoustic repertoires of other
Gryllus (see below), (2) the stridulatory apparatus is similar to that of other
Gryllus (Nickle and Walker 1974), and (3) no "silent" stridulatory movements
were noticed.
Courtship songs are produced by ovisopis males in the same circumstances
and with the same readiness as such songs are produced by other Gryllus spp.
Furthermore the songs (Fig. 2) have the same composition, consisting of a
somewhat regular alternation of short, sharp "ticks" and sequences of less
intense pulses (Alexander 1961). The frequency spectra of the 2 types of pulses
are dramatically different-the dominant frequencies of the ticks are about 14
kHz, and those of the less intense pulses are about 4 kHz. Nocke (1972) found
similarly contrasting frequency spectra for courtship singing in Gryllus
campestris Linne.
G. ovisopis males also produce aggressive songs. The circumstances under
which such songs are produced are the same as for other Gryllus spp. However,
the frequency spectrum of the aggressive song (Fig. 3) contrasts with those of
other species. In ovisopis, aggressive stridulation consists of pulses similar to
the ticks of courtship stridulation, with the most intense frequencies near 14

Vol. 57, No. 1

Walker: Gryllus ovisopus, n.sp.




(I *i 41l h

Ur i i ,II

0o 2 I0
TIME (eeo)

Fig. 2-3. Audiospectrograms of songs of G. ovisopis. Fig. 2. Courtship song.
Male placed in jar with virgin female. Song began upon contact and continued
for 20 sec. Female then mounted and received spermatophore. Fig. 3. Aggres-
sive song. One of 2 field-collected males just placed in jar. Aggressive interac-
tion related to feeding on a piece of dog chow.

kHz. Aggressive songs of other Gryllus spp. are composed of pulses similar to
those of calling and have the bulk of the sound energy at frequencies near 4
kHz (Alexander 1961, Nocke 1972). To the human ear the aggressive song of
ovisopis is much less intense than the aggressive song of other Gryllus;
however, the human ear is much less sensitive to 14 kHz than to 4 kHz. Nocke
(1972) has demonstrated that the tympanic organs of G. campestris are most
sensitive to frequencies near 4 and 14 kHz. The tympanic organs of ovisopis
may have lost the 4 kHz optimum.
Loss of calling song has occurred independently in crickets of many
phyletic lines. Even if only Florida examples are considered, there are species
representing mute genera in otherwise noisy subfamilies (Oligacanthropus
prograptus Rehn and.Hebard, Mogoplistinae; Tafalisca lurida Walker,
Eneopterinae; Falcicula hebardi Rehn, Trigonidiinae), there are mute species
in otherwise noisy genera (Scapteriscus abbreviatus Scudder vs. S. vicinus


The Florida Entomologist

Scudder and S. acletus Rehn and Hebard, Gryllotalpinae; Hapithus
brevipennis Saussure vs. H. agitator Uhler and H. undescribed sp.,
Eneopterinae), and there are mute demes of otherwise noisy species (northern
populations of H. agitator lack a calling song-Alexander and Otte 1967; the
population of Gryllus fultoni on Key Largo apparently lacks a functional
calling song-Walker, unpublished).
With so many examples, one would hope to find a common circumstance to
which to attribute loss of long-range acoustically assisted pair formation. The
principal one apparent to me is that such species are sedentary. Of the 8 mute
or partially mute species named above, all but T. lurida have lost the ability to
fly. Sedentary populations characteristically occupy relatively permanent
habitats (because such populations can evolve only in such habitats) and are
not subject to the extreme fluctuations in density of breeding adults
characteristic of temporary habitats. Consequently chance encounters or
short-range signals become more dependable pair-forming techniques.
Two other circumstances may have contributed to loss of song in ovisopis:
(1) Relatively few species call in October and November in sites supporting
ovisopis. Consequently acoustically orienting predators might destroy a
higher proportion of calling crickets than at other seasons (Walker 1964). (2)
The calling song of the earliest ovisopis may have been confusingly similar to
that of fultoni. If fultoni was more numerous than ovisopis, ovisopis may have
changed in both song and mating season in response to interference from
fultoni. The mating season of ovisopis now scarcely overlaps that of fultoni
(Fig. 1).
A circumstance that should often correlate with loss of calling song is
restricted breeding season. If individuals find mates only through chance
encounters, selection will more strongly favor those that time their readiness
to mate to coincide with maximum density of mate-ready adults of the op-
posite sex. Breeding adults of mute crickets are difficult to census, but the data
on ovisopis and other north Florida Gryllus are adequate to demonstrate that
ovisopis is much more highly restricted in its breeding season than the other 3
species. Of the 54 ovisopis juveniles reared to maturity in sheltered jars out-
doors in 1972 (Table 1), all became adult during a 5-week period, and 34
matured in the median 2 weeks (10-24 Sept.). Although there are peaks of
adult emergence in G. fultoni, firmus, and rubens, in each of these species some
emergence occurs during at least 7 months (unpublished data).


The geographical distribution of ovisopis may prove to be much more
extensive than presently known (see list of paratypes). However, its southern
limits are unlikely to change because mesic broadleaf woods are sparse south
of Gainesville. Northward it is probably restricted to the southeastern coastal
plain, but except for Fulton's failure to find it in North Carolina the evidence
is inadequate.
G. fultoni is probably the nearest relative of ovisopis. G. ovisopis was
confused with fultoni rather than with some other species largely because of
similar habitats. However, 2 other similarities support the hypothesis of ful-
toni and ovisopis having a recent common ancestor: (1) both are 100%
micropterous (except for a few jar-reared fultoni), and (2) fultoni is a less
persistent singer than most other Gryllus spp. (but not ovisopis). However,

Vol. 57, No. 1

Walker: Gryllus ovisopus, n.sp.

both of these similarities could stem from woods being a relatively permanent
habitat capable of continually supporting dense populations of Gryllus spp.
Gryllus firmus may prove to be a closer relative of ovisopis than fultoni. It
has egg diapause (as well as mid-juvenile diapause), some individuals are as
large as those of ovisopis, and the spacing of the file teeth is similarly close
(Nickle and Walker 1974, Fig. 10).
Reconstructing the evolutionary history of ovisopis is made difficult by
not knowing whether it shares a more recent common ancestry with firmus or
with fultoni. If it be firmus, speciation is more easily attributed to geographical
than to seasonal isolation. Both ovisopis and firmus are egg overwinterers, but
firmus has its principal distribution to the south of ovisopis. Its adaptations to
the sandy, burning-prone habitats of south Florida instead of the more equi-
table hammocks to the north agree with the geographical hypothesis.
On the other hand, if ovisopis proves closer to fultoni, the circumstances
are reversed and speciation is more easily attributed to seasonal isolation
(Alexander 1968). The geographical distribution of ovisopis is completely
within that of fultoni and offers no support for geographical speciation. The
seasonal life cycles, however, suggest that seasonal isolation was an essential
part of the speciation process. The life cycle of fultoni at Gainesville has the
very features that a common ancestor of fultoni and ovisopis should have: The
partial late summer generation produces eggs that hatch into juveniles that
either perish or contribute to the adult generation of the following spring.
Evidence given above suggests that eggs laid later than September contribute
little or nothing, because the juveniles that hatch in late fall die before
reaching a winter-hardy stage. The evidence given above also suggests (and
genetic theory supports) that occasional fall eggs (especially late ones?) hatch
the following spring. These hatchlings would most likely become adults in the
fall, at which time the laying of slow-to-hatch eggs would be adaptive. Fall
adults that came from overwintering eggs would have a greater likelihood of
producing reproductively successful progeny if they mated with like
adults-rather than with adults of juvenile-overwintering parentage. As a
consequence the reproductive behavior of the egg-overwintering fall adults
and that of the other fall adults would be expected to diverge. The most
obvious feature subject to selection would be mating season. Those egg-over-
winterers that delayed mating until October and November would not only
reduce the chances of an ill-adaptive mating with a juvenile-overwinterer but
also increase the likelihood that the eggs they laid would not hatch until the
following spring. Differences in pair-forming techniques would also be
enhanced by selection, but loss of calling song by the phyletic line leading to
ovisopis would be more likely after a stable, synchronized population of egg-
overwinterers had developed.


Alexander, R. D. 1957. The taxonomy of the field crickets of the eastern
United States (Orthoptera: Gryllidae: Acheta). Ann. Ent. Soc. Amer.
Alexander, R. D. 1961. Aggressiveness, territoriality, and sexual behavior in
field crickets (Orthoptera: Gryllidae). Behaviour 17(2-3):130-223.

The Florida Entomologist

Alexander, R. D. 1968. Life cycle origins, speciation, and related phenomena in
crickets. Quart. Rev. Biol. 43(1):1-41.

Alexander, R. D., and R. S. Bigelow. 1960. Allochronic speciation in field
crickets, and a new species, A cheta veletis. Evolution 14(3):334-346.

Alexander, R. D., and D. Otte. 1967. Cannibalism during copulation in the
brown bush cricket, Hapithus agitator (Gryllidae). Fla. Ent. 50:79-87.

Alexander, R. D., and T. J. Walker. 1962. Two introduced field crickets new to
eastern United States (Orthoptera: Gryllidae). Ann. Ent. Soc. Amer.

Fulton, B. B. 1952. Speciation in the field cricket. Evolution 6(3):283-295.

Laessle, A. M. 1942. The plant communities of the Welaka area. Univ. Fla.
Pub., Biol. Sci. Ser. 4(1):1-143.

Nickle, D. A., and T. J. Walker. 1974. A morphological key to field crickets of
southeastern United States (Orthoptera: Gryllidae: Gryllus). Fla. Ent.

Nocke, H. 1972. Physiological aspects of sound communication in crickets
(Gryllus campestris L.). J. Comp. Physiol. 80:141-162.

Rehn, J. A. G., and M. Hebard. 1915. The genus Gryllus (Orthoptera) as found
in America. Proc. Acad. Nat. Sci. Philadelphia 67:293-322.

Walker, T. J. 1964. Experimental demonstration of a cat locating orthopteran
prey by the prey's calling song. Fla. Ent. 47:163-165.

DIDS-(Prepublished abstract) Individuals of Ancistrocercus inficitus
(Walker) roost in association with nests of five genera of wasps in Costa Rica.
The wasps (Polistes, Stelopolybia, Polybia, Mischocyttarus and Synoeca) ap-
parently afford these otherwise defenseless tettigoniids with some measure of
protection from predators and/or parasites. Individual orthopterans are
faithful to particular nests until disturbed. (Amer. Midland Nat., 1973,
89(2):451-455; J. F. Downhower and D. E. Wilson, Ohio S. Univ., Columbus
43210 and Nat. Mus. Natur. Hist., Washington, D. C. 20560).

Vol. 57, No. 1



Systematic Entomology Laboratory, Agricultural Research Service
USDA, c/o U. S. National Museum, Washington, D. C. 20560
and Department of Entomology, University of Florida
Gainesville, Florida 32601, respectively


Culicoides edeni n. sp. is described from peninsular Florida. Characters are
given to separate it from Culicoides haematopotus Malloch, a closely related,
widespread, North American species that also occurs in northern Florida.

We take this opportunity to name and describe a new species of Culicoides
Latreille from peninsular Florida in order to make the name available for a
forthcoming review of the Florida sand flies and for another general paper on
the haematopotus Group to which it belongs. Our terminology is explained in
previous papers in this journal (see Wirth and Blanton 1971).

Culicoides edeni Wirth and Blanton, New Species
(Fig. 1)
Culicoides haematopotus Malloch (misidentified, in part); Beck, 1952:106 (in
part, south Florida records); Foote and Pratt, 1954:23 (in part, south
Florida records); Beck, 1956:134 (in part, south Florida records).
FEMALE.-Wing length 1.12 mm.
Head: Eyes (Fig. Id) narrowly to moderately separated, bare. Antenna
(Fig. la) with lengths of flagellar segments in proportion of
25-16-17-18-20-20-20-20-45-50-53-57-72; AR 1.78; sensory pattern variable,
usually 3,10-15, sensoria sometimes also present on 5, 7,9. Palpus (Fig. Ib) with
lengths of segments in proportion of 15-27-50-12-20; third segment moderately
swollen, PR 2.2, sensory pit shallow with large round opening. Proboscis
moderately long, P/H Ratio 0.83; mandible with 15 teeth.
Thorax: Yellowish brown, with heavy pale gray pollinosity; mesonotum
with pattern of narrow, irregular, dark brown, longitudinal markings present.
Legs (Fig. Ig) pale yellowish brown, knee spots blackish, no distinct dark
brown bands present; tibial comb with 4 spines, that nearest the spur longest.
Wing (Fig. Ic): Pattern nearly identical with that of haematopotus, but
not quite as distinct, the ground color of the wing somewhat paler; in addition
to the pale markings found in haematopotus, wing is characterized by a pale
area across costal cell from r-m crossvein to costal margin, and a distinct pale

'This investigation was supported in part by U. S. Army Medical Department Contract No.
'Research Associates, Florida State Collection of Arthropods, Division of Plant Industry, Florida
Department of Agriculture and Consumer Services.

24 The Florida Entomologist Vol. 57, No. 1

spot near wing margin in proximal portion of anal cell. Macrotrichia long and
numerous, extending nearly to bases of medial and anal cells; CR 0.58. Halter
Abdomen: Pale yellowish. Spermathecae (Fig. If) 2 plus rudimentary third
and prominent sclerotized ring of characteristic shape; functional sper-
mathecae unequal, measuring 0.061 by 0.038 mm and 0.054 by 0.032 mm,
including the long sclerotized necks; spermathecae slightly broader in
proportion to length than in haematopotus.
MALE GENITALIA (Fig. le, h): Indistinguishable from those of haema-
DISTRIBUTION: Bahamas, Florida.

0 -Q

O /

I \

;I| ,
y .
\I F -, .j,,

Wirth and Blanton: Culicoides edeni, n.sp.

TYPES: Holotype female and allotype male: FLORIDA: Orange Co., Rock
Springs, 21 April 1970, W. W. Wirth, light trap (Type no. 71483, USNM).
Paratypes, 23 males, 65 females, as follows:
BAHAMAS: South Bimini Island, May 1951, M. Cazier and W. Gertsch, 1
FLORIDA: Alachua Co., Gainesville, May, August 1967, F. S. Blanton, light
trap, 3 males, 1 female; 27 April 1970, W. W. Wirth, light trap, 1 female. Citrus
Co., Crystal River, 18 September 1950, Hudson, light trap, 3 females. Collier
Co., Ochopee, September 1971, F. S. Blanton, light trap, 1 female. Escambia
Co., Innerarity Point, 29 April 1949, Rathert, light trap, 3 males, 16 females.
Glades Co., Palmdale, 14 July 1970, E. Irons, light trap, 1 female. Gulf Co., St.
Joseph St. Park, 1-3 May 1970, W. W. Wirth, light trap, 13 females. Hardee
Co., Ona, July 1970, E. Irons, light trap, 1 female. Highlands Co., Lake Placid,
19 April 1970, J. N. Layne, light trap, 1 male; Highlands Hammock St. Park, 15
April 1970, W. W. Wirth, light trap, 1 male, 2 females; Archbold Biol. Sta., 3-19
April 1970, W. W. Wirth, light trap, 2 females. Lee Co., Fort Myers, 20
December 1949, Keith, light trap, 2 females. Manatee Co., Bradenton, 3
December 1948, Parnu, light trap, 2 females. Marion Co., Juniper Springs, 28
April 1970, W. W. Wirth, light trap, 1 male, 1 female. Orange Co., Lake
Magnolia Park, 6 August 1970, E. Irons, light trap, 1 male, 2 females; Rock
Springs, 21 April 1970, W. W. Wirth, reared spring margin, 5 males, pupae;
same, light trap, 2 males, 6 females; Wekiwa Springs, 16 August 1951, W. and
J. Keller, W. W. Wirth reared, 1 male, 1 female. Palm Beach Co., Morrison
Field, 20 December 1942, D. E. Hardy, 1 female; Lake Worth, Congress Road
Canal, August 1951, W. W. Wirth, reared canal margin, 2 males, 2 females.
Volusia Co., New Smyrna Beach, 22 October 1942, USDA light trap, 2 females.
Wakulla Co., Ochlockonee River St. Park, 29 April 1970, W. W. Wirth, light
trap, 3 males, 3 females. Walton Co., Grayton Beach, 10 May 1949, Butler,
light trap, 1 female.
DIScuSSION: We dedicate this species with pleasure to Dr. William G.
Eden, Department of Entomology, University of Florida, in appreciation of
his constant and enthusiastic support of our research on Florida Culicoides,
and in tribute to his many important contributions to Florida Entomology.
Culicoides edeni is very similar to haematopotus Malloch and was con-
fused with it for many years. Malloch's species, which is widespread in North
America, can be distinguished from edeni by its darker color, with dark brown
thorax and legs, and by the wing markings, in which the pale spot over the r-m
crossvein does not extend to the costal margin, and the proximal pale spot
near the wing margin in the anal cell is lacking or indistinct. The pupa of
haematopotus is larger and darker in color than in edeni, with spines better
developed, the area between the am tubercles bearing moderate to distinct
spinelike markings ranging to distinct spines.
IMMATURE STAGES: Jones (1961) gave notes on the pupa, from Wekiwa
Springs, Florida, stating that it differs from haematopotus as follows:
"Smaller, color light brown, less spinose. Respiratory trumpet not darkened so
extensively, apex narrowly dark; both trumpets with five apical and three
basal spiracular openings. Operculum disc with few uniformly medium-sized
spines, most of these confined to lateral row on each side; area between and
beyond a.m.'s bare. Area between d.'s devoid of distinct markings."

Fig. 1. Culicoides edeni n. sp.: a-d, f-g female, e, h, male: a, antenna; b,
palpus; c, wing; d, eye separation; e, parameres; f, spermathecae; g, hind femur
and tibia; h, male genitalia, parameres removed.

26 The Florida Entomologist Vol. 57, No. 1

LARVAL HABITAT: Wirth and Keller reared edeni from mud at the margin
of the stream below Wekiwa Springs in Orange County in 1951. Wirth reared
several specimens from pupae collected on the sloping, sandy margins of a
canal on Congress Road near Lantana, Florida in August 1951. Wirth
collected pupae from sandy humus at the margins of small spring areas at
Rock Springs in Orange County in 1970.
SEASONAL DISTRIBUTION: our Florida collections are distributed between
April and December.
FLORIDA DISTRIBUTION: Culicoides edeni has seldom been taken in West
Florida, with records from Escambia and Wakulla counties, but from Jack-
sonville and Gainesville southward it becomes abundant and replaces its close
relative haematopotus entirely.


Beck, E. C. 1952. Notes on the distribution of Culicoides in Florida (Diptera,
Ceratopogonidae). Fla. Ent. 35:101-107.

Beck, E. C. 1956. A new species of Culicoides from Florida with additional
distribution data for the genus (Diptera: Heleidae). Fla. Ent.

Foote, R. H., and H. D. Pratt. 1954. The Culicoides of the eastern United
States (Diptera, Heleidae). Public Health Monog. 18:1-53; 11 pl.

Jones, R. H. 1961. Descriptions of pupae of thirteen North American species of
Culicoides (Diptera: Ceratopogonidae). Ann. Ent. Soc. Amer.

Wirth, W. W., and F. S. Blanton. 1971. New species and synonymy of Florida
Culicoides (Diptera: Ceratopogonidae). Fla. Ent. 54:73-78.



Auburn University Agricultural Experiment Station
Auburn, Alabama 36830


One hundred seventy-five plant introductions of Cucurbita were evaluated
in a series of field experiments for resistance to the pickleworm, Diaphania
nitidalis (Stoll). Distinct differences were detected in degree of pickleworm
damage among 3 species tested, C. maxima, C. moschata, and C. pepo. The
plant introductions of C. maxima and C. moschata were generally more
resistant than C. pepo although certain accessions of C. pepo sustained very
little damage by pickleworm and appear to be a promising source of resistant
germ plasm.

The pickleworm, Diaphania nitidalis (Stoll), is one of the most destructive
insect pests of cucurbits in the South Atlantic and Gulf States and oc-
casionally causes damage as far north as Iowa and Connecticut and as far west
as Oklahoma and Nebraska. Cantaloupe, cucumber, and squash are the
primary host plants of the pickleworm in Alabama. The larvae reduce plant
vigor and reduce or destroy market value of the crop by feeding in vines, stalks,
buds, flowers, and most importantly, the fruits.
It appears that the pickleworm is a subtropical insect, migrating north
when environmental conditions become favorable. Records from South
Florida show this insect to be active on wild and cultivated host plants
throughout the winter. Apparently, it does not hibernate in any form in
Alabama where the first generation larvae generally appear in small numbers
in June (Canerday and Dilbeck 1968).
Cultural practices such as plant destruction, deep plowing, crop rotation,
and trap crops have been suggested to control pickleworm or reduce injury
(Dupree et al. 1955), but generally frequent applications of an effective insec-
ticide are necessary to control this pest. Canerday (1967) found several insec-
ticides to be effective in controlling the pickleworm in Alabama. However,
because of residue problems and expense associated with the frequent insec-
ticide use, an alternate method of reducing pickleworm injury is desirable.
The importance of the pickleworm as a pest of Cucurbita, the lack of
alternate means of control, and the demonstration of resistance of certain
cultivars of squash to this insect'in North Carolina (Brett et al. 1961),

2 A portion of a thesis submitted to the Graduate Faculty of Auburn University in partial
fulfillment of the degree of Master of Science in Entomology. Accepted for publication 31 August
3 Present address: Agricultural Agent, Cooperative Extension Service, Univ. of Florida IFAS, St.
Augustine, Florida 32084.
Present address: Assoc. Prof. and Dep. Head, respectively, Dep. of Entomology and Fisheries,
Univ. of Georgia, Coastal PlainExp. Sta., Tifton, Georgia 31794.

The Florida Entomologist

prompted this study to evaluate plant introductions of Cucurbita for resist-
ance to the pickleworm, and to investigate the possibility of developing a
pickleworm-resistant and horticulturally acceptable cultivar of Cucurbita.

Plant introductions of Cucurbita were evaluated for resistance to the
pickleworm in field experiments during 1967 and 1968 on the Auburn Univer-
sity Agricultural Experiment Substations at Cullman, Clanton, and
Headland, Alabama. In 1967, 130 Cucurbita plant introductions were screened
for pickleworm resistance in non-replicated plantings at these 3 locations.
Partial results of this work were presented by Dilbeck and Canerday (1968);
however, due to the high levels of resistance noted among certain entries, more
detailed data are presented here to facilitate future work. Thirteen plant
introductions that exhibited resistance to the pickleworm in 1967 were
evaluated in a replicated field experiment in 1968 at Cullman, Alabama.
Forty-five additional plant introductions were evaluated in 1968 in a non-
replicated experiment at Clanton. Seed were supplied by the Regional Plant
Introduction Stations at Experiment, Georgia and Ames, Iowa. Resistant and
susceptible cultivars were included in each plant introduction experiment to
serve as standards for selecting resistant accessions. All accessions were field
seeded in 1-row plots 30 ft. long. Rows were spaced 88 in. apart. Hills were
spaced at 3 ft. intervals and each hill was thinned to 2 plants. Tiers of plots
were separated by 3 ft. alleys, and in the replicated test in 1968, 4 replications
in a randomized complete block design were used. Squashes were harvested
weekly at bloom-drop for infestation determinations. The number of damaged
fruits per sample and the number of feeding entries per damaged squash were
recorded. Data were taken over a period of approximately 6 weeks for each
experiment. Plantings in the various tests were made from June to August to
expose the accessions to varying population levels of pickleworms.
The possibility of developing a pickleworm-resistant and horticulturally
acceptable cultivar of Cucurbita was investigated by making a series of crosses
in 1967-68. Cucurbita used in the crosses were grown in the greenhouse to
exclude any pollinating agents. Pollinations were made by hand in the early
morning. Hybrids of successful crosses were evaluated for pickleworm resist-
ance in both replicated and non-replicated experiments in 1968.


Damage sustained by 175 accessions ranged from 0 to 100% under several
different levels of pickleworm population pressure among 6 experiments at 3
locations. Examples of each species, plant type, and fruit color were selected to
show the various degrees of resistance exhibited by the accessions (Table 1).
Yields of 10 fruits or less were considered to be too low for valid comparisons,
thus these accessions were omitted.
Four accessions escaped injury and several others sustained less damage
than the resistant standard Butternut. Several of these accessions were con-
sidered to have sufficiently desirable horticultural characteristics and
pickleworm resistance to warrant further consideration. One accession, C.
maxima 265557 from Argentina, appeared particularly promising due to its
total escape from pickleworm damage, apparent disease resistance, and good

Vol. 57, No. 1

Dilbeck et al.: Pickleworm Resistance in Cucurbita



x No.
Total No. entries/ x
PI Plant Fruit fruits damaged damaged
No. Origin Species type color harvested fruit fruit

Iran C. pepo
N. Dakota
Mexico C. mosc
Argentina C. maxi
Turkey C. mosc
X ESC F,** C. pepo
Turkey C. mosc





C. pepo
C. pepo

C. maxima
C. pepo



Vine Buff 348 1.7tt 20.7tt
Vine Tan 205 3.0 t 30.1t



* X of 2 experiments.
** F, hybrid from PI 172872 x Early Summer Crookneck.
t X of 3 experiments.
St X of 6 experiments.

fruit and fruiting characteristics. Fruits were green, oblate and 3 x 5 inches in
size. Accession 172872, C. pepo from Turkey, compared favorably with the
susceptible standard, Early Summer Crookneck and was selected for crosses
with this standard. Mean damage to the F, hybrids from the cross, P. I. 172872
x Early Summer Crookneck was 11.9% with 1.8 entries per damaged squash
and was less than that sustained by either parent.





The Florida Entomologist

The data presented in Table 1 indicate certain general trends in the in-
cidence of pickleworm damage. To show these, various species from all
experiments were grouped and the mean % damage and number of entries for
each fruit color and plant type was noted (Table 2). C. moschata and C.
maxima accessions usually were damaged less than the C. pepo accessions and
vining accessions sustained less damage than the bush type. There was no
clear preference for any of the fruit colors. These observations agree with
those reported for Cucurbita cultivars (Dilbeck and Canerday 1968).

TYPES AND FRUIT COLORS IN C. maxima, C. moschata, AND C

Total X No. X %
Fruit Plant No. fruits entries/ damaged
color type harvested damaged fruit fruit




C. maxima


C. moschata

C. pepo




*Data are means from non-replicated plots at various locations.

Promising accessions were further evaluated in a replicated experiment at
Cullman in 1968 (Table 3). Two C. moschata accessions, 211998 and 169415,
sustained significantly less damage than the susceptible standard, Early





Vol. 57, No. 1

Dilbeck et al.: Pickleworm Resistance in Cucurbita

Summer Crookneck; however, these were not significantly different from the
resistant standard, Butternut, under light pickleworm population pressure.



ALABAMA, 1968.

Accession XNo.
No. fruits entries/ X %
PI Plant Fruit har- damaged damaged
no. Origin Species type color vested* fruit fruit**

211998 Turkey C. moschata Vine Green 39 1.0 1.0 a
169415 Turkey C. moschata Vine Gray 31 1.0 1.1 ab
Butternut C. moschata Vine Buff 174 1.0 2.4 a-c
135371 Canada C. moschata Vine Green 76 1.5 4.2 a-d
174178 Turkey C. moschata Vine Gray 1446 1.6 4.3 a-d
PI 172872 X
E.S. Crookneck F, C. pepo Vine Buff 515 1.6 4.9 a-e
E.S. Crookneckt C. pepo Bush Yellow 559 1.4 5.1 a-f
136449 Turkey C. moschata Vine Green 107 1.3 5.7 a-f
172872 Turkey C. pepo Vine Tan 168 1.5 6.6 a-g
158990 U.S. Africa C. moschata Vine Cream 162 2.2 8.5 b-g
162889 Paraguay C. moschata Vine Cream 70 2.3 10.3 c-g
174190 Turkey C. pepo Vine Tan 227 2.3 11.0 c-g
173684 Turkey C. pepo Bush Buff 62 4.7 11.9 d-g
E.S. Crookneck C. pepo Bush Yellow 504 1.8 12.3 d-g
183232 Egypt C. pepo Bush Green 140 2.2 13.8 d-g
181757 Turkey C. pepo Vine Tan 164 2.7 16.0 f-g
93458 Turkey C. pepo Bush Buff 153 5.1 18.1 g

*Squash harvested 7/20, 8/6, 8/15, 8/20, 8/27, 9/4.
**Percentages were transformed to angles for analysis; means followed by the same letter do not
differ significantly at the 0.05 level by Duncan's Multiple Range Test.
t Treated weekly with insecticide for pickleworm control.


Brett, C. H., C. L. McCombs, and D. M. Daugherty. 1961. Resistance of squash
varieties to the pickleworm and the value of resistance to insecticidal
control. J. Econ. Ent. 54:1191-7.

Canerday, T. D. 1967. Control of the pickleworm on cucurbits. J. Econ. Ent.

Canerday, T. D., and J. D. Dilbeck. 1968. The pickleworm: Its control on
cucurbits in Alabama. Ala. Agr. Exp. Sta. Bull. 381.

The Florida Entomologist

Dilbeck, J. D., and T. D. Canerday. 1968. Resistance of Cucurbita to the
pickleworm. J. Econ. Ent. 61:1410-13.

Dupree, M., T. L. Bissell, and C. M. Beckham. 1955. The pickleworm and its
control. Ga. Agr. Exp. Sta. Bull. N. S. 5.

Duncan, D. B. 1955. Multiple range and multiple F tests. Biometrics 11:1-42.

The Florida Entomologist 57(1) 1974

TION?-(Note) "If a hymenopterann) female is fertilized by only 1 male all
the sperm she receives is genetically identical. Thus, although the relationship
of a mother to her daughters has the normal value of 1/2, the relationship
between daughters is 3/4.... other things being equal, (a newly adult daughter
would prefer) returning to her mother's (nest) and provisioning a cell for the
rearing of an extra sister to provisioning a cell for a daughter of her own. From
this point of view therefore it seems not surprising that social life appears to
have had several independent origins in this group of insects . ." (W. D.
Hamilton, J. Theoret. Biol. 7:1-16; 17-52, 1964).


If a monogamous mother
Queen bee's daughter
Always would rather
Help her mother
Raise up other
Sister's because they're
Three-fourths like her,
Then must we mourn her
Poor queen daughter
Molded by mother
To rear only another
Mere queen daughter
Half like her?

And if the hymenop mater
Is a manipulator
Is the termite mother

R. D. Alexander,
Univ. of Michigan, Ann Arbor, 48104.

Vol. 57, No. 1



University of Florida, AREC Quincy and
Clemson University, Department of Entomology
Clemson, South Carolina

Studies of Pseudoplusia includes (Walker) larvae as prey and an im-
ported predator, Sycanus indagator (Stal) were made in field cages over
soybean plants. Predation by 3rd and 4th nymphal instars accounted for 6 to
20% larval mortality after 2 days. Other tests showed about equal results 4
days after introduction of prey and predator on soybeans. Survival of S.
indagator in soybean fields was below 50% and nymphs consumed about 1
soybean looper/day with a mean of 29 larvae during predator development.
Egg hatch for S. indagator was 93% in the laboratory and was 42% when egg
masses were pinned to soybean plants in the field.
Predation by S. indagator on cabbage looper larvae, Trichoplusia ni
(Htibner), ranged from 29 to 79% in field cages over cabbage plants. Observa-
tions of S. indagator feeding on T. ni larvae on cabbage plants showed 48.5% of
the larvae were successfully attacked in cages compared to 69% in plastic
Survival and larval consumption was too low to suggest success of this
predator in Florida cabbage or soybean fields.

The ability of introduced predators to survive and successfully seek out
their prey is basic to the success of a biological pest control program using
exotic control agents. Messenger and van den Bosch (1971) reviewed requisites
of introduced biological control agents with particular emphasis upon their
adaptability to new environments. Logical early steps in the consideration of
new or imported predator species are studies of their life history and feeding
habits (Greene 1973). Later studies should determine their ability to survive in
the field, predation potential, functional response, or changes in the number of
prey consumed by individual predators (Solomon 1949). The latter is
especially important in inundative release programs.
These experiments were designed to investigate the predation potential of
an imported predator, Sycanus indagator (Stal), on cabbage looper larvae,
Trichoplusia ni (Htibner), and soybean looper larvae, Pseudoplusia includes
(Walker), on cabbage and soybeans, respectively. Additional studies deter-
mined field survival of S. indagator in the soybean ecosystem.

'Hemiptera: Reduviidae.
2Florida Agricultural Experiment Station Journal Series No. 5002.

The Florida Entomologist

S. indagator used for these experiments were imported from India through
the Parasite Introduction and Release Station, USDA, Moorestown, N.J. W.
J. Lewis of Tifton, Georgia, supplied the stock culture for these studies during
1971. Field tests with soybean loopers were conducted at Quincy, Florida,
using cages 6 x 6 x 6 ft. covered with 18 x 14 mesh saran. The cages were in
a 2-acre field and covered 2 rows of soybeans 36 in. apart. Caged plants were
inspected regularly and were considered insect-free, but earwigs, mostly
Labidura riparia Pallas, were common on the ground inside the cages. Three
replications were used for each test with a fourth cage as a check with only
host larvae present. Two soybean looper larvae, and 1 S. indagator were put
on each of the 50 to 65 plants in each cage. The looper instar used generally
corresponded to the instar of S. indagator used in the cages. The predators
and host insects were counted 2 and 4 days after release into the cages.
Field cage experiments using cabbage loopers as prey were conducted at
Sanford, Florida. Cages (6 X 6 X 6 ft.) were placed over cabbage plants and
two 3rd or 4th-instar loopers were placed on each plant. An unreplicated cage
test to determine predation potential in the field was carried out by in-
troducing adults of S. indagator at 5, 10, and 20 per cage with 1 cage receiving
only looper larvae. Another set of 3 cages each held 20 S. indagator/cage with
1 looper per plant plus a control cage set up as before. Loopers and predators
were counted 4 or 6 days after introduction of prey and predators.
Other tests at Sanford were conducted in 3 x 3 x 4 ft. screen cages with 4
potted cabbage plants per cage. A single 5th-instar cabbage looper and 1 adult
S. indagator were randomly placed on each plant. Searching and feeding times
were recorded for 4-hr. periods with a total of 31 individuals observed.
The functional response of 5th-instar and adult S. indagator to 5th-instar
cabbage loopers was studied under laboratory conditions in plastic containers
(2.5 x 11 cm) which served as the universe. Each container contained 1, 3, or
6, 5th-instar loopers, (representing diet levels 1, 2, and 3 respectively) along
with a 5th-instar or adult S. indagator. The dead loopers were removed and
recorded daily from each container and replaced with live ones. Each treat-
ment was carried out for either 4 or 7 days with 5 to 15 replications of each.
A rearing study was conducted using 17 bugs held in individual 1/2-pint
pasteboard ice cream cartons with a glass petri dish top. The number and size
of soybean looper larvae attacked by each instar was recorded.
Egg masses were placed on soybean plants in the field and checked for
survival. Each egg mass was laid on the pasteboard rearing container and a
piece (ca. 1 in.2) with 60 to 85 eggs was cut from the container and pinned to the
underside of a soybean leaf. Egg masses returned to the lab were checked and
the emerging nymphs counted.

One group of 3rd- and 4th-instar predator nymphs placed on soybean
plants July 3 along with soybean loopers did not alter larval survival. Counts
of the 102 to 130 larvae per cage showed 80, 87, and 94% survival 2 days later
and 43 to 54% survival 4 days after introduction. Cages without predators had
fewer larvae 4 days after introduction than did cages containing S. indagator.
A second set of tests, begun August 16, resulted in 3 cages having higher looper
survival with S. indagator than without, 100% vs. 82%. One cage with 16

Vol. 57, No. 1

Greene and Shepard: Biology of Sycanus indigator

loopers and 8 3rd- and 4th-stage nymphs had 56% looper survival after 5 days
of feeding. Predator survival was 75% in that cage compared to 10 to 33% in
cages with higher looper survival.
Field survival and feeding efficiency of nymphs of S. indagator was low on
soybean plants. Only about 10% survived as 1st- or 2nd-nymphal instars
whereas 11 to 75% of the 3rd- and 4th-stage survived. Adult survival in 1 cage
was 57% after 5 days.
Results of field-cage experiments using cabbage loopers revealed that
predation by S. indagator averaged 44.3% in cages with 5 to 20 adult predators.
All looper larvae were recovered from the cage without S. indagator. When 20
adult predators were added to each cage with 24 or 36 looper larvae and 6 days
were allowed for predation, % larval mortality was variable (X = 53%, Table
1). Survival of S. indagator adults was high; only 2 of 95 were unaccounted for
after 6 days in field cages.


Cage Plants/cage Loopers/cage Predators/cage mortality

A 12 24 0 0
B 12 24 20 29
C 13 36 20 50
D 12 24 20 79

*Third- or 4th instar loopers placed on cabbage plants with looper mortality recorded 6 days after

Results of searching tests where 5th-instar cabbage loopers and an adult of
S. indagator were confined in a 3 x 3 x 4-ft. cage on cabbage plants are shown
in Table 2. Only 48.5% of the predators were able to successfully find the
cabbage looper during a 4-hr. test period. Predators experienced difficulty in
negotiating the cabbage leaves, i.e., the predators would often slip and fall to
the ground, especially while attacking a looper. In addition, the waxy material
which covers cabbage leaves adhered to the predators' legs and antennae
causing them to spend a large proportion of time with cleaning activities.


Mean (SD) searching Mean (+ SD) feeding % Successful
time (min) (N) time (min) (N) attacks (N)

Cabbage plant 16.39 ( 16.6) (15) 49.7 ( 30) (9) 48.5 (31)
Plastic container 14.7 ( + 12.7) (16) 50.8 ( 28.7) (16) 69 (26)

The Florida Entomologist

The number of successful attacks by S. indagator on the cabbage looper
increased (68%) when the looper and predator were confined to a 11 X 2.5 cm
plastic container (Table 2). It is interesting that the average searching and
feeding times of S. indagator were nearly the same for both container and
cabbage plant environments.
Records of the number of looper larvae eaten during development indicate
1 looper larva/2.8 days (Table 3). The number of larvae killed relates to their
size with 1st- and 2nd-instars feeding on small looper larvae. In the field
environment, small larvae would not be found as easily as large larvae.















Day Laid Eggs/Mass Days in Date No. Survival
Field percentage
11 Aug 70 0 27 Aug 56 80
12 80 4 30 Aug 72 90
13 82 9 0 0
16 85 12 3 Sept 2 2
17 74 16 3 Sept 72 97
19 Aug 64 4 0 0
19 77 8 5 Sept 69 90
19 80 12 0 0
19 75 16 5 Sept 7 9
19 58 0 3 Sept 56 97
19 85 est. 11 15 Sept 73 86
30 Aug 85 est. 11 16 Sept 61 72
85 est. 11 15 Sept 79 93
57 0 13 Sept 46 81
46 11 18 Sept 39 85
30 Aug 68 0 0
36 0 0
83 0 0
81 0 9 Sept 76 94

Vol. 57, No. 1

Greene and Shepard: Biology of Sycanus indigator 37

There was a corresponding increase in the numbers of successful attacks by
S. indagator with increasing prey density (Fig. 1). Loopers which were killed
were not always consumed, especially at higher diet levels where many prey
were attacked and fed upon with varying degrees of actual consumption. The
predator often immobilized the prey with no apparent feeding resulting. In-
terruption of feeding after insertion of the proboscis for 5 sec. by S. indagator
caused 50% mortality in 5th-instar cabbage looper larvae (n = 12). No sig-
nificant difference (P< 0.05) was observed between the feeding capacity of
5th-instar and adult S. indagator during comparable time periods.

Diet Level I --
Diet Level 2__. .
Diet Level 3.... .

80 /
2 /


40 i

20 /

I 2 3 4 5 6 7

Time (Days)

Fig. 1. Functional response of 5th-instar S. indagator to 3 diet levels of
cabbage loopers: level 1 = 1 looper/ container, level 2 = 3 loopers/ container,
level 3 = 6 loopers/ container.

The Florida Entomologist

There was a wide range in survival of egg masses on cardboard pinned to
the underside of soybean leaves (Table 4). Lady beetle, Coleomegilla
maculata (DeGeer), adults were observed eating egg masses. The percent
hatch was 51.6 for all eggs, 91.3 for laboratory held groups and 42.0 for masses
in the field. Six of 15 of the field egg masses failed to survive, suggesting that
over 50% of the egg masses would not hatch in the field since test masses were
not left in the field during total egg maturation.
In conclusion, survival of S. indagator in the field was too low to suggest
successful use of this predator in Florida soybean or cabbage fields and food
consumption was also low (1 larva per 2.8 days). Rain appeared to be quite
detrimental to survival of individuals in the field.


Greene, G. L. 1973. Biological studies of a predator, Sycanus indagator Stall:
I. Life history and feeding habits. Fla. Ent. 56:255-7.

Messenger, P. S. and R. van den Bosch. 1971. The adaptability of introduced
biological control agents. p. 68-92 In Biological Control. Ed. C. B.
Huffaker. Plenum Press, N. Y.

Solomon, M. E. 1949. The natural control of animal populations. J. Anim.
Ecol. 18:1-35.

HONEYS)-(Prepublished abstract) Florida honeys are characterized by a
combination of the following pollens: Ilex, Nyssa, Citrus, Serenoa group. To
this combination must be added: Vitis, Rhus-vernix group, Bidens group,
Sophora group, Trifolium repens group, Salix, Sambucus niger group, Quer-
cus, Myrica group, Carya, Persea group, Piperaceae/Saururaceae, Itea vir-
ginica and Bursera. Ilex, Nyssa, Citrus and pollens of the Serenoa and Rhus
vernix groups are predominant. In the 11 true Florida honeys examined, 11 to
15 pollens, out of the above mentioned combination of 18 pollens, have been
identified. All pollens found in .the samples studied, insofar as they were
approximately identified, are listed in the table. Their frequency of occurrence
is given. The following pollens are described: Carya tomentosa, Gordonia
lasianthus, Fagara rhoifolium, Melia azedarach, Rhus vernix, Ilex glabra,
Nyssa ogeche, Richardia scabra, Bidens bipinnata, Helenium tenuifolium,
Serenoa repens and Sabalpalmetto. (Apidologie, 1970, 1(3):233-269; G. Vor-
wohl, Landesantalt fiir Bienenkunde, Stuttgart-Hohenheim).

Vol. 57, No. 1



Department of Entomology and Nematology
University of Florida, Gainesville


Male and female Solenopsis invicta Buren were found on a lake surface
after a nuptial flight, and after another flight, dealate females believed to have
drifted from the lake surface were seen constructing brood chambers on the
shore. High numbers of alate and dealate female ants were found on a log jam
on a river. These ants had a high rate of mortality in the laboratory, possibly
due to a fungus infection resulting from wet conditions encountered while on
the river. Clumps of ants from mounds submerged during floods were found on
a lake and river. Some of these clumps of ants contained queens. Rivers may be
important in spreading ants from infested into uninfested areas.

The spread of Solenopsis invicta Buren usually occurs during nuptial
flights (Markin et al. 1971). In addition, rivers may play a role in the spread of
this ant, for during flooding, ants may desert submerging mounds, form a ball,
and float away (Green and Hutchins 1960). Possibly these floating clusters of
ants could establish new colonies downstream. Kannowski (1971) found
numbers of dead alate ants washed ashore after nuptial flights. During 1972
and 1973 I investigated the possibility of living fertile females and complete
colonies being distributed by rivers and lakes.
During a small localized flight of S. invicta in late May 1972, the surface of
Lake Talquin (Gadsden Co., Florida), was inspected from a canoe. In an hour,
64 male and 37 female alate ants were found. The ants were upright, upside
down, or on their sides in the water. All of the ants were alive; none had broken
off their wings as they do after descending to the land. Distribution of the ants
was not random, for at times as many as 6 could be seen at one time (they were
visible for ca 15 m) and at times none could be seen. Although fish were feeding
on surface material, none were seen taking ants. A rainstorm moved into the
area, and the inspection was terminated. Wave action caused by the storm
resulted in many of the ants breaking through the water surface and
presumably drowning. A single wet alate female was found washed ashore.
After a later flight, many S. invicta and mated females of several other
species were found constructing brood chambers on a narrow strip of sand on
the lake shore. Although some of the ants may have descended directly onto
the sand at the conclusion of the flights, the high numbers suggested that
many had floated to the shore. Heavy deposits of dead chironomids were also
seen in the beach drift.

'This work was partially supported by USDA, ARS Cooperative Agreement No. 12-14-100-10,952
2Florida Agricultural Experiment Station Journal Series No. 4996.
3Present address: Dept. of Entomol., Univ. of Georgia Exp. Sta., Experiment, Ga. 30212.

The Florida Entomologist

After hearing of handfuls of alate female S. invicta being found on a
wooden jetty near a dam through which Lake Talquin overflows into the
Ocklockonee River, I inspected log jams (Fig. 1 A) in the river and found about
2,000 alate and dealate S. invicta females in one location. Ants were in crevices
in logs, under bark, and clinging to log surfaces (Fig. 1 B, C). Some eggs were
present, but there were no other brood stages.

Fig. 1. (A) Log jam on Ochlockonee River (Liberty Co.) Florida; (B)
handful of dealate Solenopsis invicta collected from logs; (C) groups of ants
on logs.

A sample of the ants was taken to the laboratory, and 25 were held in
groups of 5 in 1 oz. paper cups containing 1/4 oz. of plaster of Paris. Cups were
held at 82F, and water was added as necessary to prevent desiccation of the
females and their brood. After 14 days, 50% of the ants had died. Only one
survived until workers were produced. At the same time, ants which had
flown, mated, and descended to the ground were held under the same condi-
tions. After 28 days, 88% of these ants were still alive, and workers were
produced in all cups. Usually when there was more than one queen in a cup,
the queens would fight after the workers were produced, and only one queen

Vol. 57, No. 1

Morrill: Dispersal of Fire Ants

The high mortality of the ants collected on the river is believed due to
fungal attack, for fungal mycelia appeared on the ants soon after death. When
newly mated queens were held under saturated conditions similar to those
found in the water-soaked logs, none survived. When canopies develop in
infested fields which have been replanted or grow back to trees, S. invicta
colonies are not able to survive. Perhaps the shade and high relative humidity
encourage fungal growth; mounds are built higher under these conditions.
The construction of the mound provides a gradient of temperature and
humidity under usual conditions (Green 1952).
After heavy rains in April 1973, several lakes and rivers were examined for
clumps of ants which might have escaped from submerged mounds. Clumps of
ants were found on Lake lamonia (Leon Co., Florida). Flooding had begun 14
days before the search, and it is believed the ants had been on the surface since
flooding began. The clumps of ants had floated into weeds and shrubs which
protruded above the water (Fig. 2 B). Eleven clumps of 600-5,400 ants were
collected in plastic bags, frozen, and examined. Mated queens were found in 2
clumps. The clumps were easily fragmented during collection, and it is likely
that workers from a single colony had divided into several groups after leaving
the mound. None of the clumps collected from the lake surface contained
brood, but brood and alate females were found in a clump of ants which had
moved up on a tree trunk (Fig. 2 A). Possibly after 2 weeks, the brood in the
other clumps had died and been discarded or had been eaten.

A '

Fig. 2. (A) Mass of Solenopsis invicta workers, brood, and alate forms
accumulated on tree trunk after a flood; (B) clump of ants attached to shrub
after a flood.

During this time of flooding, a large dish-shaped clump of ants was found
floating down the Suwannee River (Suwannee Co.). The clump was ca 45 cm
in diameter, and brood was visible in its center (personal communication with

The Florida Entomologist

C. F. Zeigler, Box 4970, Jacksonville, Fla. 32201). This river flows in a general
north to south direction, or in the same direction as the spread of the red
imported fire ant in Florida.
Unless a lake is unusually large and extends from infested to uninfested
land, it would be unimportant in spreading ants. However rivers may carry
mated females or (during floods) entire colonies downstream.

The author is indebted to Jon Reid, Walter Tschinkel, and Donny Harris
for assistance during collecting.


Green, H. B. 1952. Biology and control of the imported fire ant in Mississippi.
J. Econ. Ent. 45:593-7.

Green, H. B. and R. E. Hutchins. 1960. Laboratory study of toxicity of im-
ported fire ants to bluegill fish. J. Econ. Ent. 53:1137-8.

Kannowski, P. B. 1971. Unusual occurrence of winged ants in beach drift.
Prairie Natur. 3:61-4.

Markin, G. P., J. H. Diller, S. O. Hill, M. S. Blum, and H. H. Hermann. 1971.
Nuptial flight ranges of the imported fire ant, Solenopsis saevissima
richteri (Hymenoptera: Formicidae). J. Georgia Ent. Soc. 6:145-6.

Vol. 57, No. I



Department of Entomology and Nematology
University of Florida, Gainesville, Florida 32611 and
Department of Statistics
University of Florida, Gainesville, Florida 32611


Multiple regression models were formulated for 6 species of cockroaches
representing the order Orthoptera and 4 species of adult and immature
blood-feeding insects representing the orders Anoplura, Diptera, and
Hemiptera. Results from multiple regression analyses indicated that the total
body concentration of 2 major elements (i.e. K and Na for cockroaches and Mg
and Na for blood feeding insects) could effectively be used to estimate or
predict the acute (LD,01/4 hr) radiosensitivity of insects on a species level.

Data have been presented by Levy et al. (1973) indicating the importance
of total body concentrations of several major and trace elements in predicting
or estimating the acute radiation mortality (LD50/24 hr exposure) of insects on
a species level. Simple regression analyses of these data indicated that statis-
tically significant estimates of species-specific LDso/4 hr exposures could be
made when insects were subdivided into groups based on their laboratory
diets. The following groups with their associated elemental bioindicator were
used: cockroaches, K; blood feeders, Mg; stored product beetles, Cu or Cu/Fe
Major and trace elements do not always act alone in performing their
biological functions (Christian and Feldman 1970, Comar and Bronner 1962,
Schitte 1964). There is sometimes an interelement dependence, and the ef-
fects of 1 element may be dependent on the presence and concentrations of
another. The simultaneous actions of the alkali metals Na and K, as well as
other metals such as the alkaline earths (i.e. Mg), have been shown to be
responsible for maintaining a proper balance in cellular metabolism. A
physiological relationship has been shown between Mg and Na and K and Na
for insects (Chapman 1969).
The current study explores the feasibility of utilizing the importance and
interelement dependence of Na(Na+) with other biologically active cations i.e.
Mg(Mg2*) and K(K+), in the physiology of insects to improve the acute
(LDo/,,2 hr) radiation exposure predictions for the cockroach and blood feeders
models (Levy et al. 1973). Hence, multiple regression models would be tested
using total body concentrations of K and Na for cockroaches and Mg and Na
for blood feeders. This multi-elemental approach is hoped to further reduce
the variations encountered between the observed and predicted radiation
exposures for related species of insects having similar diets.

'Florida Agricultural Experiment Station Journal Series No. 5003.
'Department of Entomology and Nematology, University of Florida, Gainesville, Florida 32611.
3Department of Statistics, University of Florida, Gainesville, Florida 32611.

44 The Florida Entomologist Vol. 57, No. 1

Parts per million Na, K, and Mg for each insect in the cockroach and blood
feeder groups (Levy et al. 1973) were determined by atomic absorption spec-
troscopy (Levy and Cromroy 1973). Acute (LD50/24 hr) exposure data for each
species in a model was obtained from previous research by Levy, et al. (in
press). Repeated sampling of adult insects from several laboratory colonies
indicated that the experimentally observed LD50/24 hr exposures were usually
within a + 20% error range, probably due to variations in sex and age within an
irradiated sample.
Statistical analyses consisted of fitting multiple regression models using
the method of least squares (Draper and Smith 1966). Multiple regres-
sion analyses of the data were based on the straight line equation, y =
bo +b,(X,) +b,(X2), where y = the estimated or predicted LD50,,, hr exposure in
Roentgens(R), bo= constant, b. ... b,=the estimate or measure of the
strength of the effect of X. ... X, on the response y, where X,.... X, = the total
body concentration of a specific major element in parts per million(ppm).
To test the strength of a predictor equation, the coefficient of multiple
determination (R2) and F-statistic (F) were calculated for each model. F-test
significance at the 0.05 level was indicated for each model. The standard error
(SE) for each predicted or estimated LD50/24 hr exposure was also determined.
Predicted LD,,,24 hr exposures and their respective standard errors were
rounded off to the nearest whole number.


Multiple regression analyses of 6 species of adult cockroaches representing
the order Orthoptera and 4 species of adult and immature insects representing
the orders Anoplura, Diptera, and Hemiptera indicated that there was an
excellent correlation between 2 major elements (i.e. K and Na for cockroaches
and Mg and Na for blood feeders) and the acute (LDso]02 hr) radiation expo-
sure for insects on a species level (Tables 1, 2).
The biological relationship between Na and K and Na and Mg in the
metabolism of insects has been discussed by Chapman (1969). In addition,
Levy et al. (in press) have shown the importance and feasibility of utilizing the
known relationship between the trace elements Cu and Fe in the form of a
Cu/Fe ratio in formulating predictor equations for stored product beetles.
Simple regression analyses indicated that this combination of elements (i.e.
Cu/Fe) would significantly improve the LD50/24 hr exposure predictions in the
stored product beetle model over a model based entirely on copper (Levy, et al.
in press).
The R2 values and F-statistics for the cockroach and blood feeder models
(Tables 1 and 2) indicated that the addition of the major element Na sig-
nificantly decreased the variation encountered between the observed and
predicted LD50/24 hr exposures on a species level, and therefore improved the
prediction capability of each model over its corresponding simple regression
predictor model (i.e. y= 18.5882 + 0.0056(K), R2 = 0.8797 for cockroaches and
y=172.2073-0.0147(Mg), R2=0.8798 for blood feeders) (Levy et al. in press).
This could indicate the biological importance and-interaction of Na(Na+) in
the mechanisms) involving the acute radiosensitivity of insects (Levy et al.

Levy et al.: Radiosensitivity of Insects


PREDICTOR EQUATION**. y= 18.0819 + 0.0046(K) + 0.0047(Na)

Species Total body Total body Observed Predicted
K Na LD5o/24 hr LD50/24 hr
(ppm) (ppm) (kR) + SE

Periplaneta brunnea Burmeister 15263 4653 97 109 + 7
Periplaneta americana (L.) 6194 1569 52 54+9
Blatella germanica (L.) 10956 2438 91 79+6
Leucophaea maderae (F.) 18904 2473 118 116 9
Nauphoeta cinerea (Olivier) 20293 6174 146 139 10
Periplaneta fuliginosa (Serville) 16225 2309 96 103 7
*Diet consisted mainly of PurinaS dog chow.
*R= 0.9206; F-test value (F = 17.3886) highly significant at the 0.05 level.

PREDICTOR EQUATION**: y= 134.6404-0.0117(Mg)+0.0131(Na)

Species Total body Total body Observed Predicted
Mg Na LDo5/24 hr LD0/24 hr
(ppm) (ppm) (kR) + SE

Cimex lectularius L. 368 2108 155 1583
Pediculus humanus humanus L. t 487 3280 175 172 + 3
Culex pipiens quinquefasciatus Say 1885 1810 140 136+3
Stomoxys calcitrans L. 3987 2160 115 117+4
Pediculus humanus humanustt 487 t 3280 170 172 3

*In most cases diet consisted of human, rabbit, citrated or defibrigonated blood.
**R= 0.9843; F-test value (F= 62.7649) highly significant at the 0.05 level.
t Mainly females.
tt Nymphs-all other species analyzed in the adult stage.
Based on same potassium content as adults due to analysis of the 2 stages in a mixed sample.

The authors wish to thank the Insects Affecting Man Research Labora-
tory, USDA, for their assistance in supplying and irradiating many of the
insects used in this research. This research was partly supported by NIH
Training Grant No. 1T01A100383-01 from the National Institute of Allergy
and Infectious Diseases.

The Florida Entomologist


Chapman, R. F. 1969. The Insects: Structure and Function. American
Elsevier Publishing Company, Inc., N.Y. 819 p.

Christian, G. D., and F. J. Feldman. 1970. Atomic Absorption Spectroscopy:
Applications in Agriculture, Biology, and Medicine. John Wiley & Sons,
Inc., N.Y. 490 p.

Comar, C. L., and F. Bronner. 1962. Mineral Metabolism: The Elements. Vol.
2. Part B. Academic Press, N.Y. 623 p.

Draper, N. R., andH. Smith. 1966. Applied Regression Analysis. John Wiley &
Sons, Inc., N.Y. 407 p.

Levy, R., and H. L. Cromroy. 1973. Concentration of some major and trace
elements in forty-one species of adult and immature insects determined
by atomic absorption spectroscopy. Ann. Ent. Soc. Amer. 66:523-26.

Levy, R., H. L. Cromroy, and J. A. Cornell. 1973. Major and trace elements as
bioindicators of acute insect radiosensitivity. Radiat. Res. 56:130-9.

Schitte, K. H. 1964. The Biology of the Trace Elements. J. B. Lippincott Co.,
Philadelphia. 228 p.

PA-(Prepublished abstract) Entomophagy often plays an integral and
complementary role in the diet of autochthonous groups in tropical South
America where it helps to compensate for the general deficiency of animal
proteins and other vital "protective" products. Most studies have regarded
insect-eating as an archaic trait which is gradually disappearing owing to the
steady encroachment of more modern subsistence systems. Among the Yuk-
pa-Yuko Indians of Venezuela and Colombia, however, insect foods have
retained their importance in the less acculturated communities. Cultural
ecological research was conducted among this tribe between 1969 and 1971.
Specimens for identification were procured in the areas exploited for subsis-
tence purposes by the Irapa, Maraca, and Rionegro subgroups. The collection
and use of insects belonging to 22 genera and 7 orders is discussed. (Biotropica,
1973, 5(2):94-101; K. Ruddle, University of California, Los Angeles 90024).

Vol. 57, No. 1



Vero Beach Laboratories, Vero Beach, Florida


Tetranychus tumidus Banks, is a polyphagous spider mite that can thrive
in the laboratory on over 70 host plants of various families, especially on many
belonging to the Leguminosae, Malvaceae, Compositae and Gramineae; those
in the Solanaceae appear unpalatable. The female mite developed slowly at
190C and required 21.5 days (20 for male) as compared to its development at
290C which required 8 days (7.5 days for male). At 24C the average daily rate
of oviposition (4.21 eggs) and average number of eggs per female lifespan (49.67
eggs) were both higher than at 19 and 290C. Optimal temperatures appeared to
be closer to 24 than to 290C. Field populations appeared in spring once morn-
ing low temperatures climbed into the upper teens and day-time highs into the
twenties. Populations decreased in early summer and virtually disappeared
when rains appearing in May and June established, together with the high
temperature, optimal conditions for a spider mite fungus, Entomophthora,
epidemic. Precipitation also reduced the population mechanically if occurring
at 3 in. or more per 24 hr. The population remained practically negligible until
early autumn when precipitation ceased. The 2nd population growth in au-
tumn was halted and its decline commenced once temperatures dropped in
October, or if prior to that, optimal conditions for fungus infection were
established again. Phytoseiulus macropilis (Banks) was the only predator
found in significant numbers among several predatory species recorded.

The tumid spider mite, Tetranychus tumidus Banks, was described by
Banks (1900) from water hyacinth in Florida. Since then it has been reported
from Georgia (Flechtmann and Hunter 1971), Tennessee (Rodriquez et al.
1957), Louisiana (Roussel et al. 1951) and westward from Texas (Ivy and
Scales 1954) and Arizona (Bibby and Tuttle 1959) to California. It is also
found to the south in Mexico, Puerto Rico, Bermuda, Guam, and Trinidad
(Pritchard and Baker 1955) as well as in Hawaii (Prasad 1967).
Since 1900 T. tumidus was described and known under the following
synonyms: T. quinquenychus McGregor (1914), T. antillarum Banks, Sep-
tanychus quinquenychus (McGregor), and S. tumidus McGregor (Pritchard
and Baker 1955). Boudreaux (1958a) showed that T. gloveri Banks is not a
synonym of T. tumidus as had been-presumed, but is a separate species.
T. tumidus has been reported to be a serious pest of vegetable crops, field
crops, and ornamentals in some areas. However, it can occur on a suitable host
plant such as cotton in such climatically different areas as Arizona and

'Received for Publication 16 July 1973.
present Address: Direction de la Recherche Agronomique, Phytiatrie, B.P. 415, Rabat, Morocco.
3Acaricidal evaluations on T. tumidus in Florida. Internal report to Bayer AG.

The Florida Entomologist

Florida and yet be of no economic importance. In other areas it has reduced
the seed cotton yield by 45% (Roussel et al. 1951). Moreover, natural popula-
tion increases in greenhouses in Vero Beach, Florida can cause severe plant
damage at any time of the year on various crops if control measures are not
All reports on the occurrence of the tumid spider mite which required
chemical control in the field, or where field populations were introduced into
the laboratory for toxicological evaluations, showed the population strains to
be susceptible to acaricides and/or insecticides with acaricidal properties (Ivy
et al. 1957 in Texas, Mistric 1957 in North Carolina, Abo-El-Ghar and
Boudreaux 1958 in Louisiana, Abid and Ridgway 1969 in Texas, Saba 1968 in
Florida). No acaricidal resistance has been reported from the field to date. In
1 case, a laboratory culture was found to have developed a certain degree of
tolerance to parathion, probably through unintentional emission of certain
organo-phosphorus fumes in a confined area (Ivy and Scales 1954). However,
this tolerance might have been more a case of vigor tolerance than one of
chemical resistance, because in spring of the following year this tolerance
Very little is known about the biology and behavior of T. tumidus.
Boudreaux (1958b) in research on the effect of high vs. low humidity on
oviposition and egg hatch was not able to explain why T. tumidus did not have
reactions similar to those of other tetranychid species. Rodriquez et al. (1957)
studied the development of tumid mite populations in correlation with the
nutritional content of valentine beans that had been grown in soil treated with
chlorinated hydrocarbons. To the best of my knowledge, no other information
on T. tumidus is available. I conducted studies on the biology under controlled
conditions in the laboratory. In addition, I studied a field population at Vero
Beach and its relation to a variety of host plants available throughout 2 years
and to the occurrence of natural enemies. Also, abiotic factors that influenced
the population were noted. The inter-relationship between all these factors
and their influence on the spider mite population throughout the year are
I used dwarf lima bean, Phaseolus lunatus L., var. Henderson, as the food
plant for my studies of the life history of the tumid spider mite in the labora-
tory. The mite culture originated from specimens taken from cotton fields in
Vero Beach in the summer of 1966 and reared continuously on beans; it is now
known as the "VBL-Saba strain". Oviposition counts were conducted by
confining the spider mite in a cage (Saba 1971a) on a mite-free primary bean
leaf, which in turn was kept fresh for days on sterilized absorbent cotton in 100
mm petri dishes. The cotton was wetted daily with tap water. Once the leaf
showed signs of deterioration, the female was transferred to a fresh leaf.
Studies on development and longevity were conducted on young lima bean
seedlings with roots intact and kept fresh in 60 ml bottles filled with tap water.
Egg and post embryonic development were studied at 19 + 1, 24 + 1, and 29 +
1C. The feasibility of studying the host plant range of the tumid spider mite
under field conditions was not practical, therefore plants were removed with
their root system fairly intact, potted, and placed in a conditioned room.
Thereafter, a well infested bean leaf with all stages of the mite was taken from
the VBL-Saba strain culture and set on the plant. One week later, an evalua-

Vol. 57, No. 1

Saba: Biology of Tetranychus tumidus

tion of the degree of infestation was made. The plant was either not a host
plant and rated as such with a minus (-) sign or served as only a poor one ( + );
otherwise it supported a good (+ +) or very good (+ + +) population and so
proved to be a suitable host.
Development.-Eggs from virgin females (producing only males) and eggs
of fertilized females that developed into females required equal time periods
for development (Table 1). At 290C this period was 3.5 days; but at lower
temperatures the period was longer, 12 days at 190C. The post embryonic
development commences with the larval stage, and passes through 2 nymphal
and 3 chrysalis stages before the spider mite emerges as an adult male or
female. However, time differences in the post embryonic development
between the sexes did appear. The female required 0.5-1.5 days longer to reach
the adult stage than the male; this post embryonic development was
temperature dependent and was more pronounced as temperatures were
lowered. The total period required for a male or female to develop was ca. 3
times longer at 190C (32 and 33.5 days for the male and female, respectively)
than at 29'C (11 and 11.5 days, respectively). The ratio of egg development
time to that of the post embryonic stages at 190C (1:1.8) was not equal to that
at 290C (1:2.3). The egg developed relatively slower at low temperatures than
the post embryonic stages did, but relatively faster at higher temperatures.
Mating.-Copulation normally took place immediately after the female
emerged from the teleochrysalis. Often the male, which emerged before the
female, could be seen close to or on top of the teleochrysalis stage. Copulation
lasted ca. 1 min. The preoviposition period was 1 day at 24 and 290C, and 2
days at 190C, and was not influenced by mating. Older females also mated. A
15-day-old female that stopped laying eggs, mated; however, no renewed
oviposition was observed. Males copulated more than once and mated at an
older age. Females of this species are parthenogenetic.
Female longevity.-Twenty general females were kept at 19 + 1, 24 + 1,
and 29 + 10C for studies on longevity and oviposition. The longest life span
was at 190C where 50% of the females lived for 21 days, and 10% for over 40
days. Fig. 1 also shows female longevity at 24 and 290C, temperatures that
20 ----
............ 9 C

.. -. -.... ... .. ---.. 2*C

5 10 15 20 25 30 35 40 45
Female Longevity iff Days
Fig. 1. Longevity of female T. tumidus at 3 different temperatures in 1970.

50 The Florida Entomologist Vol. 57, No. 1

prevail in Florida during spring through autumn months, as well as on many
days of the mild winter months. There was no pronounced difference in
longevity at those temperatures, but the female does live slightly longer at 24
than at 290C; at 190, significant differences were obtained (Table 1).
Oviposition.-After a preoviposition period of ca. 1 day, virgin females lay
reddish eggs and fertilized females white eggs. The oviposition period was
shorter the higher the temperature, and in most cases was directly related to
adult longevity, although some females lived for over a week at 24 and 290C,
and for over 2 weeks at 190C after laying their last egg. The pattern of egg
laying was very similar to that of Tetranychus yusti McGregor (Saba 1971a)
and T. urticae Koch (Saba 1961a). A high peak was reached between the 2nd
and 5th days, then gradually leveled off; however, this peak was less
pronounced at 190C and extended over 8 days.
The average daily oviposition and average number of eggs at 19, 24, and
290C are shown in Table 1. It appears that the total number of eggs per female
life span was also temperature dependent. The average oviposition rate of 20
females at 24 and 290C was about equal, 49.67 and 41.3 eggs, respectively, but
at 190C it was clearly less with only 28.05 eggs per life span. Oviposition
differences are also reflected in the highest number of eggs laid per female on
any day, as well as in the average daily oviposition. It appears from the results
obtained at 19, 24 and 290C as to longevity and oviposition, that the optimal
temperature for T. tumidus lies between 24 and 290C, but probably closer to
the former temperature.
Host plant spectrum.-The tumid spider mite has been reported from
several ornamentals and field crops but the extent of its host plant spectrum
had never been measured. To understand the population dynamics of this
species in the field a knowledge of its host plants during the entire year is
essential for reasons discussed hereinafter. The age of the plant and/or leaf
can determine if a selected host is suitable or not. Four plant species were
selected for closer observation: cotton, horse weed, para grass, and purslane.
When old plants from the field with only fully mature or old leaves were
infested in the laboratory, the mites dispersed and left the plant. Once younger
plants of these 4 species were infested, the spider mite population thrived. On
the other hand, very young leaves of some plant species do not serve as hosts as
is the case with squash. Nevertheless, there are some plant species that can
serve as hosts irrespective of plant or leaf age or maturity; among these hosts
are red and sweet clover.
The role of the age or maturity of the leaves in determining if and when a
plant species may serve as a host may be determined by mechanical factors
such as leaf texture or form (waxy cuticulae, hair density, curled leaves, etc.)
or by inadequate nutritional composition of the leaf, or by both factors com-
bined. Under field conditions, the mite can be selective because at practically
any time of the year suitable host plants are available at Vero Beach. Table 2
lists the plants tested to determine their suitability as host plants. The mite is
undoubtedly polyphagous and can thrive during any month of the year on
several suitable plants. Table 2 also indicates in which season the plants
develop at Vero Beach and are therefore available. The table does not list all
weeds, grasses, or vines in the vicinity but most of the more common species
found on the premises of the Vero Beach Laboratories.
Of the plants evaluated, many Gramineae, Leguminosae, Compositae, and
Malvaceae proved to be favorable hosts, whereas those in the Solanaceae

o, >i


















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The Florida Entomologist

T. tumidus.

Family and Species

Thelypterus kunthii
Parietaria praetermissa (Nutt.)
Fagopyrum esculentum Moench
Molluga verticillata L.
Rumex acetosella L.
R. crispus L.
Phytolacca americana L.
Portulaca oleracea L.
Portulaca oleracea L.
Drymaria cordata (Willd.)
Beta vulgaris L.
Chenopodium album L.
C. giganteum
Amaranthus blitoides S. Wats
A. spinosus L.
Persea americana Mill.
Fumaria officinalis L.
Brassicajuncea (L.) Czern. et Coss.

B. oleracea L.
Rorippa teres
Rosa hybrids
Archis hypogaea L.
Crotalaria sagittalis (L.)
Desmodium canum (Desv.)
D. triflorum D.C.
Glycine max (L.) Merr.
Lupine hirsutus L.
Melilotus alba var. uban Desrousseaux
Phaseolus lunatus L.
P. vulgaris L.

Common Name

Wood fern


Carpet weed
Sheep sorrel
Curled dock

Poke weed


Red beet
Lambs quarter

Season of Host Plant
Vegetation* Suitability*


F+W +

F + W +++
S + F
F+W -

AY +++

F+S +++t
F + S ++ f

F+W +++


+ f

Spreading pigweed AY
Spiny pigweed AY


+ t

Common fumitory F + W

Florida broad-
leaf mustard



Sweet clover
Lima bean
Valentine bean

F +W+S


S + F
S + F
F + S


+ +

+ +

+ + +

Vol. 57, No. 1

Saba: Biology of Tetranychus tumidus

Family and Species

Common Name

Sesbania exaltata (Raf.)
Stizolobium deeringianum (Bort.)
Trifolium pratense L.
T. repens L.
Vigna sinensis (L.) Savi ex Hassk.
Geranium carolinianum (L.)
Pelargonium sp.
Linum usitatissimum L.
Ricinus communis L.
Euphorbia maculata L.
Abelmoschus esculentus L.
Gossypium hirsutum L.
Gossypium hirsutum L.
Sida rhombifolia L.
Urena lobata L.
Cucurbita maxima Duch.
Cucumis sativus L.
Ammannia latifolia
Ludwigia sp. (prob. palustris L.)
L. erecta
Hydrocotyle umbellata (L.)
Rhododendrum japonicum Suring
Asclepias curassavica L.
A. syriaca L.
Richardia scabra (L.)
Calonyction aculeatum (L.) House
Ipomoea purpurea (L.) Roth
Clerodendrum fragrans (Vent.) R. Br.
Lantana camera L.
Hyptis mutabilis (Rich.) Briq.
Mentha piperita L.
Nicotiana tabacum L.
Physalis angulata L.

Velvet bean
Red clover
White clover
Cow pea

Crane bill


Castor bean

Caesar weed


Dollar weed



Florida pusley

Moonflower vine
Morning glory

Season of Host Plant
Vegetation* Suitability**
S+F +++
F+W +++
W + S +++
S + F +++

F+W +++
AY +

F+W +


S + F
S + F


+++ tt

AY +++
AY +++


F+W ++
AY ++ ft








AY +++

AY +++


Ground cherry

+ +

S+F +
F + S ++

The Florida Entomologist

Family and Species

Common Name

Vol. 57, No. 1

Season of Host Plant
Vegetation* Suitability**

Lycopersicum esculentum L.
Solanum nigrum L.
S. tuberosum L.
Bacopa manner
Linaria canadensis (L.) Dum.
Blechum brownei (L.)
Ruellia brittoniana
Thunbergia alata Boj. ex Sims
Plantago sp.
Ambrosia artemisifolia L.
Anthemis cotula L.
Bidenspilosa L.
Chrysanthemum segetum L.
Conyza (Erigeron) annuus
Conyza (Erigeron) annuus
C. canadensis L.
Dahlia sp.
Eclipta alba Hassk.
Eclipta alba Hassk.
Emilia javanica
Erechtites hieracifolia
Erigeron quercifolius
Erigeron quercifolius
Gnaphalium falcatum (L.)

G. peregrinum (Fern.)

Helianthus annuus L.
Soliva pterosperma (Ruiz. et Pav.)
Sonchus asper Hill

S. oleraceus L.

Eichhornia crassipes (Mart.) Solms
Commelina diffusa Burm

Lolium temulentum L.
Stenotaphrum secundatum (Walt.) O.
Hordeum vulgare L.

Black nightshade
Irish potato

Blue toadflax

Dog fennel
Spanish needles
Daisy fleabane
Daisy fleabane
Mares tail

narrow leaf

Common sow-

Water hyacinth

Common day-

Darnel (ryegrass)
St. Augustine





F + S



+ + +.

+ + +
+ + +*

+ t
+++ tt
+ t

F+W ++

F+S ++
F+W ++
F+W ++

F+W ++

AY ++


F+W +++


Saba: Biology of Tetranychus tumidus

Family and Species

Common Name

Secale cereal L.
Triticum sativum L.
Avena sativa L.
Eleusine indica Gaertn.
Cynodon dactylon Persoon
Dactyloctenium aegyptium Willd.
Digitaris sanguinalis (L.) Scop.
Echinochloa colonum (L.) Link
E. crusgalli L.
E. frumentacea Link
Panicum purpurascens Raddi.
Panicum purpurascens Raddi.
Paspalum dilatatum Poir.
P. distichum L.
P. notatum
P. urvillei
Rhynchelytrum repens (Willd.)
C. E. Hubb
Sorghum bicolor (L.) Moench
,remochloa ophiuroides (Munro)
Zea mays L.
Palmae spp.
Cyperus compressus (L.)
C. rotundus L.

C. surinamensis (L.)
C. surinamensis (L.)

Winter wheat



Bermuda grass
Crowfoot grass

Large crabgrass
Jungle rice
Barnyard grass
Japanese millet
Para grass
Para grass
Dallis grass
Bahia grass
Vasey grass
Natal grass


Centipede grass

Season of Host Plant
Vegetation* Suitability**

F + W
F + W

+ + +

F+W -
S+F ++
S + F + +



+ +

+ +


+ tt


S+F ++

S+F -



Purple nut-

++ +


S + SU +
AY +

SU + F ++ +t
SU + F -

*AY= practically all year; W= winter (January to February); S=spring (March to May); SU=-
summer (June to September); F =fall (October to December).
*- = no feeding; + = poor host plant; + + = good host plant; + + + = very good host plant.

t cited in literature

tt young plants
t old plants

ft mature plants

The Florida Entomologist

appeared not to be suitable. The classification of plants in Table 2 is according
to Engler (1964). The common names, some of which are probably not
approved, were obtained from various sources. For most Monocotyledoneae
common names Ward (1968) was used as a reference.
Insecticidal and acaricidal susceptability.-Samples of the field popula-
tion were reared in the laboratory and evaluated as to their susceptibility to
insecticides and acaricides. The test method of evaluating the response to
toxicants was described by Saba (1971b) and the compounds selected for that
evaluation were azinphosmethyl, oxythioquinox, and ethion.
The LC5o and LC,, as well as the heterogeneity quotient for the 3 com-
pounds are given in Table 3. Heterogeneity quotient is a term coined by
Moericke and Saba (Saba 1961b) as an expression of how the individual mites
within a population respond to toxicants. It is calculated by dividing the LC,,
by the LC,,. The lower the quotient the more homogeneous would be the
population towards a certain chemical. This information could be of value
also in predicting potential development of resistance to acaricides and insec-
ticides in that particular population or strain. The tumid spider mite popula-
tion tested is susceptible to all 3 compounds (Table 3). In evaluation of the
response of adult females to oxythioquinox, a strong repellent effect of that
compound was observed because many females migrated away from treated
bean leaves. The mortality data for oxythioquinox (Table 3) include those
females that migrated.

tumidus TO 3 TOXICANTS.


LCso LCg, Hetero- LCo LC,, Hetero-
Toxicant geneity geneity
quotient quotient

Azinphosmethyl 0.00024 0.00073 3.0 0.00013 0.00043 3.3
Oxythioquinox .00026 .0026 10.0 .00005 .00038 7.6
Ethion .00016 .00034 2.1 .0011 .0038 3.4

Because in acaricidal control the residual efficacy of a compound on the
whole population is usually more important than the initial control, more
emphasis is to be put on the ovicidal effect of an acaricide than that on the
initial mobile stages. The effectiveness of oxythioquinox as an ovicide was
superior to that of azinphosmethyl and ethion.

Fieldpopulation.-Several crops are grown in the fields of the Vero Beach
Laboratories, but cotton is the only one on which a noticeable population of

Vol. 57, No. I

Saba: Biology of Tetranychus tumidus 57

tumid spider mites develops. Cotton plants are retained in autumn each year,
cut back, and fertilized about mid February mainly to obtain early foliage
growth for experimental trials in spring and/or to allow for early feeding and
reproduction sites for Anthonomus grandis Boheman. By the beginning of
March, good foliage is already present which could support a natural spider
mite infestation. The cotton then remains in good condition, if well cared for,
through September and until the 1st cold spell in October. I examined such
cotton fields from 1968 through 1971 for spider mite populations. In the 1st 2
years, I noted heavy infestations during April and May and again towards the
end of August until October, but not during June-August on cotton.
In 1970, a cotton field was selected for closer studies on the population
dynamics of T. tumidus. Five rows of cotton showing early signs of spider mite
infestation were marked and at almost weekly intervals 200 leaves (40/row)
were collected from them at random. In the laboratory the mites were brushed
off the leaves onto a plastic disc by means of a brushing machine. Those discs
were then evaluated under binoculars as to the number of spider mites and
other mites available per cotton row.
The growth and decline of a tumid spider mite population in conjunction
with some factors influencing it is shown in Fig. 2.

--- Spider Mite Population & Maximum Temperature in"C
- Spider Mtes. Eggs 0 Minimum Temperature ,
0- 0 Predacious Mites T Daily Rainfoll

4000- 2 2. ee 0 -2 Z
7000 0 .

1000 Ai 3 0 .5
0 25 0 5 0 15 20 25 30 1
S/ .e 4 0

00 I ne 1 1.
ooo / T 0.5

April May June 1970

Fig. 2. Influence of precipitation, drought, and predaceous mites on a
spring population of T. tumidus in a cotton field at Vero Beach, Fla.

The temperature was quite low during February and March 1970, with
morning temperature usually below 15'C up to 27 Mar.; whereas the daytime
high rose into the 20's after mid-February. However, the spider mites appeared
in 1970 at the beginning of April. In April and May the morning lows remained
usually in the upper teens, and the daytime high temperatures were regularly
in the upper 20's or low 30's. The tumid spider mites increased up to 37
mites/leaf by 21 Apr. (Fig. 2). The whole population, estimated number of eggs
included, increased almost parallel to that of the mites.

58 The Florida Entomologist Vol. 57, No. 1

Rainfall in Vero Beach did not occur from 5 Apr. through 24 May and
irrigation of the cotton field became necessary. This field was overhead
irrigated on 22 Apr. equivalent to 3 in. of rainfall. Those 3 in. markedly
diminished the population to 15.5 mites/leaf when evaluated on 28 Apr. The
gradual population increase in the beginning of May was halted by 2 factors
occurring during the latter part of that month; the cotton plants began to wilt
and new growth had halted, and secondly predaceous mites present in April at
the ratio of 1 predaceous mite to 27 spider mites increased to the ratio of 1
predaceous mite to 10 spider mites by 18 May. The only predator available in
any appreciable number was Phytoseiulus macropilis (Banks), although oc-
casionally few individuals of other phytoseid species were found. From June
on and throughout the summer the spider mites were hardly noticeable in
spite of available good host plants. The strong influence of rainfall on the
population was worth looking into again, since precipitation is normal for the
summer months in Florida.
In mid-August the spider mites reappeared and the population increased
once more to 6.3 mites/leaf as evaluated on 11 Sept. (Fig. 3).

Spider Mite Population
S Mmlmum Temprature In' C
A MH mum Temperure .
.- raLy ear Temperature -
700 T OlIvy Ralnfattn Inrche

.-- .. . .
300- \ I -5-
i iI * *'

T0 i i A A-

5 to 15 20 25 30 5 10 15 20 25 30 1 -5
ptembr Octobe November 1970

Fig. 3. Influence of precipitation and temperature on an autumn popula-
tion of T. tumidus in a cotton field at Vero Beach, Fla.

The mean daily temperatures were in the 20's throughout September and
October with the temperature lows also in the 20's. No predaceous mites were
recorded in that field. Rainfall was registered on 28 days, 2 days of which
accounted for precipitation of ca. 3 in. The immediate effect of those heavy
rainfalls was again the diminishing factor of the number of spider mites per
leaf. On 13 Sept., precipitation was 2.83 in., and the number of mites was
reduced from 6.3/leaf on 11 Sept. to 1.0/leaf on 17 Sept. (Fig. 3). On 29/30 Sept.
the number fell once more to 0.9/leaf after precipitations of 4.5 in, within 48 hr.
Individual light rainfalls were observed not to diminish the population dras-
tically even if occurring on consecutive days.
tically even if occurring on consecutive days.

Saba: Biology of Tetranychus tumidus 59

Towards the end of October, the morning low temperature began to drop
and by the beginning of November the daily mean temperature dropped
markedly and the cotton leaves became old and unsuitable as host plants. The
spider mite population gradually diminished from mid October on.
In spring of 1971, cool temperatures prevailed also in the beginning of
April, and the tumid spider mite population began increasing towards the
latter part of the month and reached a peak of 220 mites/leaf by mid-May. On
14, 15 and 16 May a total of 2.61 in. of rainfall was recorded. The spider mite
population thereafter decreased rapidly to 40 spider mites/leaf on 27 May and
to 0.05/leaf on 3 June.
The number of eggs per 200 leaves was exactly counted, not estimated as in
spring of 1970. The ratios of number of eggs to number of postembryonic stages
were almost alternatingly 2 eggs to 1 stage and 3 eggs to 1 stage according to
the weekly evaluations (Fig. 4). Once the population rapidly declined the ratio
of eggs to stages declined to 1.7 eggs to 1 stage and 1.3 eggs to 1 stage by the end
of May 1971.

-- Spider Mite Population
*--. Spider Mite Population Eggs
o Minimum Temperature in OC
a Maximum Temperature in C
-i- Daily Rainfall in Inches

56000- 6 .25o 3-
A,- 3 06

O0 O0
5, 0 0 \ 250 15
a0 1 0 0 0 5 2

a / ti at ~a
3 'a 00) 0
e0 0 r a 0 \,
E 2000 \ 10- 1"

z oo T 5
1ooo T, 0 / T- 5T-
5 10 15 20 25 30 5 10 15 20 25 30 5 10
April May June 1971

Fig. 4. Influence of Entomophthora sp., precipitation, and temperature on
a spring population of T. tumidus in a cotton field at Vero Beach, Fla.

The heavy rainfall of 15 May could not have been the direct cause for that
complete population decline within 2 weeks. Other predators available besides
P. macropilis were to a much lesser extent Scolothrips sexmaculatus (Per-
gande) and an anthocorid, as well as the 2 coccinellids Hippodamia conver-
gens Guerin-Meneville and Cycloneda immaculate (F.). However, laboratory
observations of either coccinellid were not conclusive as to their predation on
spider mites. P. macropilis was more numerous than any of the predators,
averaging 50 mites/100 leaves picked at random during the peak of the spider

The Florida Entomologist

mite population, as compared to 6 S. sexmaculatus/100 leaves and 2 of each of
the other species per 100 leaves. Once the spider mite population disappeared
on 3 June, none of the 5 predators was found either.
The rapid decline of the population towards the end of May 1971 must
have been influenced by yet another factor, because all 5 predators were not
available in such large numbers to account for a decimation. The possibility of
a fungus disease having decimated the population could not be excluded,
because high humidity as well as high temperatures after that rainfall on 15
May prevailed. Samples of living and dead spider mites were collected and sent
for verification and identification of a fungus disease. The results confirmed a
fungal infestation of over 60% of the living female samples studied by the end
of May 1971. The fungus was identified as an Entomophthora sp.


The tumid spider mite is a polyphagous species found mainly on low-
growing plants and is able to survive on several available suitable host plants
throughout the year. The factors influencing its population dynamics are of
both biotic and abiotic nature; those limiting its population growth, or even
reducing it to a minimum during certain seasons in Florida are often based on
a combination of more than 1 of the following factors: prolonged low
temperatures in winter, heavy rainfalls, availability and especially condition
of host plants, predators and diseases, besides plant protection measures.
In the mild winter months of Florida the development of the spider mite is
slow. Temperatures during some nights can dip below the freezing point for
several hours, although usually remaining above 0C and daytime tempera-
tures range between 5 and 250C.
Because this species appears to have no form of diapause in Florida (as
observed by the author), its development is only temporarily halted during
low temperature spells. Once the daytime temperature rises above 200C and
night temperatures climb into the upper teens for several consecutive days,
even immediately following nights with temperatures below or ca. 0C, spider
mites, almost exclusively adult females, are observed already feeding and
ovipositing on young leaves. From April through to October, the temperatures
are suitable for the development of the tumid spider mite if other limiting
factors were not available. In October, once the night temperatures drop to
the lower teens, development decelerates. Low temperatures retard the
embryonic development more than that of the postembryonic one, and
probably the embryonic stage contributes more effectively to the survival of
the species during the cool spells of the winter months.
Precipitation occurs regularly during the summer months from May
through September, but occasional rains have been recorded during each
month of the year. When heavy rainfall of 3 in. or more per 24 hr. occurs, alone
or in combination with very strong winds, many immature spider mites fall off
the leaves and are either injured or incapable of attaining the same host plant,
and thus contribute markedly to the mechanical reduction of the population.
Rainfall on consecutive days may have other negative effects on the popula-
tion, but were not studied here; Linke (1953) in studying the effect of very high
humidities in the laboratory on T. urticae, observed a lethal effect of extreme

Vol. 57, No. 1

Saba: Biology of Tetranychus tumidus

prolonged humidities on the larval and young nymphal stages. Boudreaux
(1958b) observed that T. tumidus under constant high humidities did not have
a reduced life span or oviposition as several other tetranychid species.
However, the extreme conditions under which Linke conducted his trials do
not correspond to natural conditions prevailing in Florida. It could also well
be that T. tumidus can withstand higher humidities better than other te-
tranychid species, or that its optimal relative humidity lies much higher than
that of other species.
The indirect effect of rainfall, if heavy or even light on consecutive days on
the spider mite population can be of a far greater impact than the direct
mechanical one mentioned above. Under certain circumstances when
prevailing high temperatures coincide with high humidities formed through
precipitation, conditions for optimal Entomophthora fungal growth occur and
the population could be decimated within ca. 1 week. Such conditions may
occur twice yearly that will cause an immediate breakdown in the field
population: in early summer (May/June) and in autumn (Sept./Oct.). Those
coinciding climatic factors appear to contribute substantially to the practical
disappearance of the tumid spider mite throughout the warm and rainy
summer months in Florida, the humid subtropics and tropics, and probably
southeastern United States. Entomophthora species have been recorded in-
festing several Acarina; for example E. floridana Weiser and Muma was found
attacking Eutetranychus banksi (McGregor) from citrus (Weiser and Muma
1966) and Selhime and Muma (1966) studied its biology; and E. fresenii
Nowakowski was found attacking T. urticae and T. cinnabarinus Boisduval
(Carner and Canerday 1968).
The role of the host plant on the population dynamics of the tumid spider
mite is not to be underestimated. There are enough hosts available
throughout the entire year for this species to thrive on. Suitable plants having
only a short vegetative period support a population but do not contribute to
heavy population densities. A large population develops especially well on
suitable host plants with relatively high vegetational growth over a long
period of time, such as cotton, okra, horse weed, castor bean, etc. One reason
for such population increases is that the larval and nymphal stages rarely
migrate, but once having completed their development the adults will transfer
faster and in larger numbers to the newer and more optimal succulent leaves
of the same plant than if they would have to migrate in search for a new host
because the present one attained maturity within a short period. Also, once a
plant gets prematurely old or new growth is halted because of droughts, the
female spider mites will migrate in search for more optimal nutrition and so
the population density is again affected.
Other factors of biotic nature influencing the population are diseases,
parasites, and predators. The fungus disease mentioned hereinbefore in rela-
tion to rainfall is probably endemic in the humid subtropics and causes severe
infestation once optimal conditions prevail. I did not encounter any zoological
parasites of T. tumidus but several predators. The only predator encountered
in 5 years which was available yearly in high numbers was P. macropilis, and
to a much lesser extent some species of Hemiptera, Diptera, and Coleoptera.
A closer study of the Entomopthora fungus disease and that of the
predaceous mite P. macropilis and their relationship to the tumid spider mite
especially in the field is worth pursuing, because each exerted a strong
influence on the tumid spider mite population.

The Florida Entomologist

I express sincere thanks to the following who assisted in verification or
identification of species: H. Denmark, Florida, for Acarina; M. Muma, Florida
and E. Mueller-Koegler, Germany, for Entomophthora; E. Rowehl, VBL,
Florida, for several host plants.


Abid, M. K., and R. L. Ridgeway. 1969. Mortality, longevity, and fecundity of
spider mites on cotton treated with systemic acaricides. J. Econ. Ent.

Abo-El-Ghar, M. R., and H. B. Boudreaux. 1958. Comparative responses of
five species of spider mites to four acaricides. J. Econ. Ent. 51:518-22.

Banks, N. 1900. The spider mites of the United States (Tetranychus and
Stigmaeus). USDA Div. Ent.; Tech. Ser. Bull. 8. p. 65-77.

Bibby, F. F., and D. M. Tuttle. 1959. Notes on phytophagous and predatory
mites of Arizona. J. Econ. Ent. 52:186-90.

Boudreaux, H. B. 1958a. Tetranychus tumidus Banks versus Tetranychus
gloveri Banks (Acarina: Tetranychidae). Ann. Ent. Soc. Amer.

Boudreaux, H. B. 1958b. The effect of relative humidity on egg-laying,
hatching, and survival in various spider mites. J. Insect Physiol.

Carner, G. R., and T. D. Canerday. 1968. Field and laboratory investigations
with Entomophthora fresenii, a pathogen of Tetranychus spp. J. Econ.
Ent. 61:956-59.

Engler, A. 1964. Syllabus der Pflanzenfamilien. II Band. Gebrueder Born-
traeger, Berlin-Nikolassee. 666 p.

Flechtmann, C. H., and P. E. Hunter. 1971. The spider mites (Prostigmata,
Tetranychidae) of Georgia. J. Ga. Ent. Soc. 6:16-30.

Ivy, E. E., and A. L. Scales. 1954. Are cotton insects becoming resistant to
insecticides? J. Econ. Ent. 47:981-4.

Ivy, E. E., A. L. Scales, and L. J. Gorzycki. 1957. A new systemic insecticide for
cotton insects. J. Econ. Ent. 50:698-9.

Linke, W. 1953. Untersuchungen ueber Biologie und Epidemiologie der
Gemeinen Spinnmilbe Tetranychus althaea v. Hanst. unter besonderer
Beruecksichtigung des Hopfens als Wirtspflanze. Hoefchen-Briefe

McGregor, E. W. 1914. Four new tetranychids. Ann. Ent. Soc. Amer. 7:354-64.

Mistric, W. J. 1957. Chemical control of Tetranychus telarius (L) and T.
cinnabarinus (Bois.) on cotton. J. Econ. Ent. 50:803-5.

Vol. 57, No. 1

Saba: Biology of Tetranychus tumidus

Prasad, V. 1967. Biology of the predatory mite Phytoseiulus macropilis in
Hawaii (Acarina: Phytoseiidae). Ann. Ent. Soc. Amer. 60:905-8.

Pritchard, E. A., and E. W. Baker. 1955. A revision of the spider mite family
Tetranychidae. Mem. Ser. 2, Pac. Coast Ent. Soc. 472 p.

Rodriguez, J. G., H. H. Chen, and W. T. Smith. 1957. Effects of soil insec-
ticides on beans, soybeans, cotton and resulting effect on mite nutri-
tion. J. Econ. Ent. 50:587-93.

Roussel, J. S., J. C. Webber, L. D. Newsom, and C. E. Smith. 1951. The effects
of infestation by the spider mite Septanychus tumidus on growth and
yield of cotton. J. Econ. Ent. 44:523-7.

Saba, F. 1961a. Ueber Entwicklung und Rueckgang der Giftresistenz bei
Tetranychus urticae Koch und deren Abhaengigkeit von der
Wirtspflanze. Z. angew. Ent. 48:265-93.

Saba, F. 1961b. Ueber die Bildung der Diapauseform bei Tetranychus urticae
Koch in Abhaengigkeit von Giftresistenz. Ent. Exp. Appl. 4:264-72.

Saba, F. 1971a. Tetranychus yusti McGregor, a spider mite of potential
economic importance. J. Econ. Ent. 64:141-4.

Saba, F. 1971b. A simple test method for evaluating response to toxicants in
mite populations. J. Econ. Ent. 64:321.

Selhime, A. G., and M. H. Muma. 1966. Biology of Entomophthora floridana
attacking Eutetranychus banksi. Fla. Ent. 49:161-8.

Ward, D. B. 1968. Checklist of the vascular flora of Florida. Part 1. Fla. Agr.
Exp. Sta. Tech. Bull. 726. 72 p.

Weiser, J., and M. H. Muma. 1966. Entomophthora floridana n. sp.
(Phycomycetes: Entomophthoraceae), a parasite of the texas citrus
mite, Eutetranychus banks. Fla. Ent. 49:155-9.


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USDA Forest Service, Southeastern Forest Experiment Station
Olustee, Florida 32072

Feeding by larvae of Dioryctria abietella (Denis & Schiffermiiller) was
stimulated by acetone extracts from conelets of slash pine, Pinus elliottii
Engelmann var. elliottii. Ether-soluble and water-soluble fractions of the
acetone extract elicited a continuous feeding response only when recombined.
Larval feeding was also induced by 0.1 M solutions of sugars applied to the test
substrate. The efficacies of sucrose, fructose, raffinose, and glucose as larval
feeding stimulants were increased by addition of the ether-soluble fraction of
the acetone extract. Maximum larval feeding, however, occurred in response
to a combination of all 4 sugars plus the ether-soluble fraction.

Dioryctria abietella (Denis & Schiffermtiller) is one of several species of
cone moths that reduce production of seed in orchards of slash pine, Pinus
elliottii Engelmann var. elliottii. One alternative to relying solely on insec-
ticides for controlling cone moths is the suppression of larval feeding on the
cones by the use of attractive baits or repellents applied to trees in seed
orchards. Such a method would be particularly applicable in seed orchards of
slash pine because of their relatively small size and high-value crops.
The role of sugars and other chemicals as feeding stimulants has been
demonstrated for several species of insects which feed on coniferous trees.
Heron (1965) found that sugars, L-proline, and alcoholic extracts of the
staminate flowers, shoots, and foliage of white spruce, Picea glauca (Moench)
Voss, evoked feeding responses in larvae of the spruce budworm, Choris-
toneura fumiferana (Clemens). The lipid components, extractable in pe-
troleum ether, were not found to be active as stimulants of larval feeding.
Adults of the pales weevil, Hylobius pales (Herbst), however, were responsive
to neutral lipids extracted from the phloem of loblolly pine, Pinus taeda L.;
these lipids produced a synergistic effect on feeding responses when combined
with sugars (Thomas and White 1971). Larvae of D. abietella were found to be
responsive to a combination of 5 sugars that occur in the conelets (first-year
cones) of slash pine (Fatzinger 1968). First-stage larvae initiated feeding
within an average time of 3.3 days on an artificial medium that contained the
5 sugars, whereas they required 6.6 days to begin feeding on the same medium
without the sugars. Under the same laboratory conditions, however, larvae
usually began feeding within 24 hr. on conelets of slash pine, which presum-
ably contained other chemical stimuli required for optimum feeding of the
This paper reports the effects of certain sugars and extracts of slash pine
conelets on the feeding responses of larvae of D. abietella.

The Florida Entomologist

Bioassays were conducted with extracts of slash pine conelets and with 0.1
M solutions of 4 of the 5 sugars that occur in the conelets. Conelets were
collected from trees growing in seed production areas near Olustee, Florida;
cone crops from these areas had histories of being highly susceptible to attacks
by Dioryctria spp. Larvae of D. abietella used in the bioassays were reared
through the third or fourth stage under a light-dark cycle of 12 hr. light: 12 hr.
darkness at 27C on scales cut from conelets of slash pine. This procedure
facilitated the removal of larvae from their food and prevented their responses
to conelet extracts from being attenuated, as might have occurred had they
been reared on artificial medium.


Freshly collected conelets were prepared for extraction by freezing them
for a minimum of 24 hr. at -50C. The frozen conelets were chopped to a coarse
powder in a blender, and 330 g of the powder was extracted with a sequential
series of solvents of increasing polarity (benzene, chloroform, acetone,
ethanol, methanol, and water) in Soxhlet extractors. The sample was ex-
tracted for 24 hr. with each solvent, and the resulting 6 extracts were concen-
trated to a volume of 250.0 ml. each in vaccuo on a rotary evaporator at 50C.
At this concentration, 5.0 ml. of each extract was equivalent to the extractives
of an average conelet weighing 6.6 g. Each extract was assumed to contain a
different group of compounds that were extracted according to the relative
polarities of the different extraction solvents. The non-polar or weakly polar
solvents, e.g., benzene, chloroform, were used to extract compounds of low
polarity such as the terpenes and lipids, whereas the more highly polar sol-
vents, e.g., methanol, water, were used to extract more polar constituents from
the conelets such as amino acids and sugars. Sequential solvent extraction was
used to minimize occurrence of the same compounds in more than one of the 6
extracts. Extracts were stored at 5C and bioassayed within 5 days.
The acetone extract was separated into an ether-soluble and a water-
soluble fraction as follows. An equal volume of water was mixed with 100.0 ml.
of an acetone extract. The acetone was evaporated from the mixture in vaccuo
at 500C, and the volume of the mixture was adjusted to 100.0 ml. by further
evaporation. The aqueous mixture was washed 3 times with 100.0 ml. of
diethyl ether in a separatory funnel, and the resulting 300.0 ml. of ether
extract was concentrated to a volume of 100.0 ml. in vaccuo at 250C. Water
insoluble materials were removed from the water-soluble fraction by filtra-
tion. As before, 5.0 ml. of each fraction was equivalent to the extractives from
1 conelet.

Feeding responses of the larvae to various sample chemicals were deter-
mined by estimating the percentage consumed of each of 5 cubes (4 mm3) of
American elder, Sambucus canadensis L., pith that had been infiltrated with
the sample chemicals. The cubes were treated by soaking them in different
sample chemicals for 30 min. in vaccuo (15 mm. Hg) and allowing the solvents
to evaporate for 24 hr. at room temperature. The treated cubes were identified
by soaking them in a different food color for each treatment and dried an

Vol. 57, No. 1

Fatzinger: Feeding Stimulants from Pine Cones

additional 24 hr. (Larval responses to color of pith were prevented by con-
ducting the experiments in total darkness and by assigning different color
codes to the same treatments between tests.)
Test arenas were glass petri dishes (1.5 cm. deep x 9.0 cm. in diam.) in
which the treated materials and 6 larvae were sandwiched between 2 pieces of
moist Whatman No. 1 filter paper (9.0 cm. diam.). For each sample chemical to
be tested, a set of 5 cubes was treated and placed in the test arena. The total
number of cubes present in each arena depended upon the number of sample
chemicals tested during a given experiment. The cubes were placed randomly
by mixing them in a large vial and pouring them into each dish. Larvae were
allowed to feed on the cubes for 72 hr. under constant darkness at 270C. The
feeding responses of the larvae to the different chemicals were analyzed by
visually estimating the percentage of each cube eaten within a test arena.
These figures were averaged for each test arena, which was considered to be a
replicate in an experiment. The treatment means were rounded to the nearest
whole percent and were subjected to an arc-sine transformation and analysis
of variance.
The bioassay of 6 extracts obtained by sequential solvent extraction con-
sisted of 41 replicate test arenas, each of which contained cubes treated with
the 6 extracts plus check cubes treated with distilled water. Additional bioas-
says were conducted with cubes treated with the acetone extract, the ether-
soluble and water-soluble fractions of the acetone extract, and 0.1 M solutions
of sucrose, glucose, fructose, and raffinose. Both fractions of the extract were
bioassayed independently and after recombination, and the ether-soluble
fraction was tested in combinations with the sugars.

Throughout the bioassays, feeding activity of the larvae was assumed to be
concentrated on cubes of pith that were treated with the optimum chemo-
stimulants available within the limits of each test arena. Although the larvae
tended to feed on most of the cubes available to them, significant differences
occurred in the amounts of feeding on cubes treated with different sample
Feeding responses to the 6 extracts obtained by sequential solvent extrac-
tion of slash pine conelets are given in Table 1. Continuous feeding occurred
only on cubes treated with the acetone extract and resulted in up to 90% of the
material being consumed within some of the test arenas. Less feeding occurred
on pith treated with the other extracts and this feeding was not continuous;
i.e., it consisted only of a series of small bites taken from the edges of the
treated cubes.
Bioassays with the 2 fractions of the acetone extract indicated that the
chemicals responsible for continuous feeding of the larvae had been separated
between the water-soluble and ether-soluble fractions of the acetone extract
(Table 2). Continuous feeding occurred on cubes treated with either the ace-
tone extract or the 2 fractions of the acetone extract recombined, but sig-
nificantly greater percentages of each cube treated with the recombined frac-
tions were consumed.
Feeding activity was greater in response to 0.1 M sucrose combined with
the ether-soluble fraction than it was to the previously tested combinations
and extracts (Table 3). Responses to the uncombined ether- and water-soluble



The Florida Entomologist Vol. 57, No. 1


Extraction solvent Mean % consumed S.E.
per cube in 41 arenas* (P = 0.05)

Acetone 35 7
Ethanol 5 a 3
Benzene 4a 1
Chloroform b 0
Methanol Ob 0
Check (distilled water) 0 b 1
Water Ob 0

*Any 2 means followed by the same letter are not significantly different at the 1% probability level
by Duncan's multiple-range test. For each chemical tested, 5 treated cubes were placed in each



Mean % consumed S.E.
Treatment per cube in 10 arenas* (P = 0.05)

Ether- and water-soluble
fractions recombined 51 17
Acetone extract 17 11
Ether-soluble fraction 2 a 2
Water-soluble fraction 1 a 1

*Any 2 means followed by the same letter are not significantly different at the 1% probability level
by Duncan's multiple-range test. For each chemical tested, 5 treated cubes were placed in each

fractions were not significantly different from the responses to the untreated
check cubes. In the presence of cubes treated with the sucrose and ether-
soluble fraction combination, there was no significant difference in feeding
response to cubes treated with the acetone extract, the recombined fractions
of the acetone extract, or 0.1 M sucrose alone. These results were inconsistent
with those of the previous bioassay in which feeding responses were sig-
nificantly different between cubes treated with the acetone extract and cubes
treated with the 2 recombined fractions (Table 2). This inconsistency ap-
peared to be a result of larvae concentrating most of their feeding on cubes
treated with the optimum chemostimulants available. During the 72-hr.
bioassay period, the larvae confined most of their feeding activity to cubes

Fatzinger: Feeding Stimulants from Pine Cones


Mean % consumed S.E.
Treatment per cube in 30 arenas* (P = 0.05)

Ether-soluble fraction
plus sucrose 36 12
Acetone extract 8 a 4
Ether- and water-soluble
fractions recombined 8 ab 6
0.1 M sucrose 8 ab 5
Ether-soluble fraction 2 b c 2
Water-soluble fraction 2 c d 2
Check (distilled water) 1 c d 1

*Any 2 means followed by the same letter are not significantly different at the 5% probability level
by Duncan's multiple-range test. For each chemical tested, 5 treated cubes were placed in each

treated with the sucrose and ether-soluble fraction combination. This re-
sponse, in turn, reduced the amount of feeding that occurred on other cubes in
:the test arenas to the extent that significant differences in feeding did not
occur between cubes treated with the acetone extract or its recombined frac-
tions. Thus, the time limit of 72 hr. was apparently insufficient to demonstrate
all interactions between multiple treatments. The bioassay did demonstrate,
however, that sucrose could be used as a substitute for the water-soluble
fraction of the acetone extract and indicated that the acetone extract and its
water-soluble fraction probably contained sugars extracted from the conelets.
Although sugars are relatively insoluble in acetone, they could have been
present in the water removed from the conelets in the acetone extract. Cubes
treated with 0.1 M sucrose appeared to contain a better concentration of sugar
for stimulating larval feeding than was present in the extract. The ether-
soluble fraction by itself did not elicit feeding responses significantly different
from the check, but it appeared to act as a synergist when combined with 0.1 M
sucrose. This phenomenon was similar to the results of Thomas and White
(1971), who first demonstrated a synergistic effect between the phloem lipid
and sucrose used to stimulate feeding of the pales weevil.
A bioassay of the ether-soluble fraction of the acetone extract in com-
binations with the 4 sugars known to occur in slash pine conelets indicated
that there were no significant differences in feeding on cubes treated with 0.1
M solutions of sucrose, raffinose, or fructose (Table 4). The least amount of
feeding occurred on cubes treated with glucose. Maximum feeding occurred on
cubes treated with the ether-soluble fraction and a solution containing 0.1 M
concentrations of all 4 of the sugars.
The results of these experiments indicated that the sugars of slash pine
conelets can serve as feeding stimulants for larvae of D. abietella. The

The Florida Entomologist



Sugars combined with Mean % consumed S.E.
ether-soluble fractions per cube in 10 arenas* (P = 0.05)

4 sugars combined 28 10
Sucrose 16 a 8
Raffinose 16 a 6
Fructose 10 a b 5
Glucose 7 b 4

*Any 2 means followed by the same letter are not significantly different at the 5% probability level
by Duncan's multiple-range test. For each chemical tested, 5 treated cubes were placed in each

stimulatory effect of these sugars was enhanced when they were combined
with other chemicals extracted from the conelets by acetone and diethyl

I am indebted to Dr. W. E. Cole of the Intermountain Forest and Range
Experiment Station and Mr. G. L. DeBarr of the Southeastern Station for
their valuable suggestions and assistance during various phases of this study.
I also wish to thank Drs. H. A. Thomas and H. O. Yates III of the Southeast-
ern Station and Dr. W. W. Neel of Mississippi State University for their
critical reviews of the paper.


Fatzinger, C. W. 1968. Rearing successive generations of Dioryctria abietella
(D. and S.) (Lepidoptera: Phycitidae) on artificial media with aspects
on nutrition of the insect. Ph. D. thesis, N.C. State Univ., Raleigh.
178 p.
Heron, R. J. 1965. The role of chemotactic stimuli in the feeding behavior of
spruce budworm larvae on white spruce. Can. J. Zool. 43:247-269.

Thomas, H. A., and J. D. White. 1971. Feeding behavior of the pales weevil,
Hylobius pales (Coleoptera: Curculionidae). I. Synergistic effects with
loblolly pine phloem extracts. Can. Ent. 103:74-79.

Vol. 57, No. 1



Systematic Entomology Laboratory
Agricultural Research Service, USDA
c/o U. S. National Museum, Washington, D. C. 20560 and
Department of Entomology, University of Florida
Gainesville, Florida 32601, respectively


Culicoides pseudopiliferus Wirth and Hubert is synonymized with C.
alexander Wirth and Hubert because of misidentification of the type
specimens of the former. The species whose female was described as
pseudopiliferus is described and figured as parapiliferus new species with
types from Long Island, New York. A redescription and figures are also given
for alexander.

Few tasks are more distasteful in taxonomy than that of calling attention
to a taxonomic error in one's own publication, especially when that error is
compounded by a faulty procedure. A year after the publication of the revision
of the eastern species of the Culicoides piliferus group by Wirth and Hubert
(1962), Wirth was able to collect and rear much additional material during a
survey of the Culicoides of New York state in 1963. Study of extensive series of
C. alexander Wirth and Hubert and C. pseudopiliferus Wirth and Hubert
showed that the reared series from Swallow Falls State Park, Garrett Co.,
Maryland, from which the holotype and allotype of pseudopiliferus were
selected, was actually conspecific with alexander. The female description of
pseudopiliferus, which was drawn up from a series of specimens from 9 states
and provinces, does not agree with the holotype specimen. As first revisers we
believe that the only valid course now open is to synonymize the 2 names, for
which we prefer to conserve the name alexander, and to rename the species
whose female was described as pseudopiliferus. The 1962 description of the
male of pseudopiliferus was from the Swallow Falls allotype, and this
description serves to characterize the male of alexander.

Culicoides parapiliferus Wirth and Blanton, n. sp.
(Fig. 1)
Culicoides pseudopiliferus Wirth and Hubert, 1962: 189 (female only;
description and figures); Jamnback, 1965: 89 (male, female redescribed;
figures; New York distribution; biology); Battle and Turner, 1971: 72
(female redescribed; figures; Virginia).
Female.-Wing length 1.15 mm.

'This investigation was supported in part by U. S. Army Medical Department Contract no.
DA-49-193-MD-2177. Approved as Florida Agricultural Experiment Station Journal Series No. 4874.

The Florida Entomologist


'' -', .. -. 4 b


g h

Fig. 1. Culicoides parapiliferus: a, female antenna; b, female palpus; c,
female wing; d, female eye separation; e, male parameres; f, male genitalia,
parameres removed; g, female spermathecae; h, femur and tibia of hind leg.

Head: Eyes (Fig. Id) broadly separated, bare. Antenna (Fig. la) with
lengths of flagellar segments in proportion of 19-13-13-14-14-
14-14-14-21-22-25-28-38; AR 1.22; sensory pattern 3,5,7,9,11,13-15,
rarely also on 10 and 12, sometimes absent on 11. Palpal segments (Fig. Ib)
with lengths in proportion of 12-25-30-13-17; PR 2.5; third segment long and
only moderately swollen, with a moderately small, shallow, round, sensory pit.
Proboscis moderately long, P/H Ratio 0.92; mandible with 17 teeth.
Thorax: Brownish black; mesonotum with faint dark gray pruinosity. Legs
(Fig. If) dark brown, femora unbanded, tibiae with faint subbasal pale rings;
tibial comb with four spines, the second from the spur longest.
Wing (Fig. Ic): Prominent pattern of distinct pale markings; pale spot over
r-m crossvein; poststigmatic pale spot at end of second radial cell; large
longitudinal pale spot filling apex of cell R5; pale spot straddling vein Ml at its
proximal third and a pale spot straddling vein M2 at midlength; pale spots at
wing margin in apices of cells Ml, M2, and M4, pale streak from base of cell
M2 to level of mediocubital fork where it broadens; pale spot at base of anal
cell near mediocubital stem, and a large pale spot in distal portion of anal cell
usually extending to posterior wing margin. Macrotrichia coarse and
moderately numerous, extending to base of wing in-cell M2 and anal cell; CR
0.59. Halter pale in dry specimens, appearing infuscated by transmitted light
on slide-mounted specimens.

Vol. 57, No. 1

Wirth and Blanton: New Culicoides Species

Abdomen: Dark brown. Spermathecae (Fig. le) 2 plus rudimentary third
and sclerotized ring; functional spermathecae oval, tapering to both ends,
without sclerotized necks; unequal, measuring 0.068 by 0.049 mm and 0.051 by
0.036 mm.
Male Genitalia (Fig. lh).-Ninth sternum with moderately deep
caudomedian excavation, the ventral membrane not spiculate; ninth tergum
moderately long and tapering, apicolateral processes moderately long, stout at
bases, pointed distally, the caudal margin between them slightly cleft. Basis-
tyle with ventral root foot-shaped, dorsal root long and slender; dististyle
moderately curved, slender distally, with bent, pointed tip. Aedeagus with
basal arch rounded, extending to 0.65 of total length, basal arms slender and
curved; distal process short with slender, rounded tip. Parameres (Fig. Ig)
each with large basal knob, midportion rather slender, distinctly sinuate,
tapering distally to sharp slender point with 4-5 distal fringing spines.
Distribution.-Eastern North America from Wisconsin to Ontario, south
to northern Florida.
Types.-Holotype, female, allotype, male, 5 female paratypes, Montauk,
Long Island, New York, 24 May 1963, W. W. Wirth, reared from margin of a
small pond (Type no. 71454, USNM).
Discussion.-Culicoides parapiliferus can be distinguished from alex-
anderi by its broader eye separation, longer proboscis (P/H Ratio 0.92),
longer third palpal segment, darker gray mesonotum, the slender rounded tip
of the distal process of the male aedeagus, and by the stouter apicolateral
processes of the male ninth tergum.
All the locality records given by Wirth and Hubert (1962) for
pseudopiliferus apply to parapiliferus, with the exception of the series from
Swallow Falls State Park and Bittinger 4H Club Camp in Garrett County,
Maryland, which are alexander. Jamnback's (1965) New York records and
Battle and Turner's (1971) Virginia records of pseudopiliferus also appear to
be correct for parapiliferus.

Culicoides alexander Wirth and Hubert
(Fig. 2)

Culicoides alexander Wirth and Hubert, 1962: 190 (female; Massachusetts;
figs.); Jamnback, 1965: 39 (redescribed; female; New York).
Culicoides pseudopiliferus Wirth and Hubert, 1962: 189 (in part, figures and
description of male only; Maryland).
Female.-Wing length 1.13 mm.
Head: Eyes (Fig. 2d) narrowly separated, bare. Antenna (Fig. 2a) with
lengths of flagellar segments in proportion of 20-14-14-14-14-
14-14-14-20-21-24-26-37; AR 1.08; sensory pattern 3,5,7,9,13-15. Palpal seg-
ments (Fig. 2b) with lengths in proportion of 8-21-22-11-14; PR 2.1; third
segment short and slightly swollen, with small, round, rather indistinct, sen-
sory pit. Proboscis relatively short, P/H ratio 0.70; mandible with 14 teeth.
Thorax: Dark brown; mesonotum with uniform dark gray pruinosity,
more grayish than in parapiliferus. Legs (Fig. 2f) brown, knee spots blackish,
indistinct pale rings before apex of fore femur and subbasally on fore and hind
tibiae; tibial comb with 4 spines, the second from the-spur longest.
Wing (Fig. 2c): Pattern of pale spots arranged as in parapiliferus but
usually less extensive and less distinct. Macrotrichia long and numerous,

The Florida Entomologist


d e

Cf h

Fig. 2. Culicoides alexander: a, female antenna; b, female palpus; c,
female wing; d, female eye separation; e, male parameres; f, female sper-
mathecae; g, femur and tibia of hind leg; h, male genitalia, parameres

extending to base of wing in cell M2 and anal cell; CR 0.59. Halter pale to
slightly infuscated.
Abdomen: Dark brown. Spermathecae (Fig. 2e) 2 plus rudimentary third
and sclerotized ring; functional spermathecae oval, without sclerotized necks;
size very unequal, measuring 0.087 by 0.062 mm and 0.053 by 0.042 mm.
Male Genitalia (Fig. 2h).-Ninth sternum with deep caudomedian ex-
cavation, the ventral membrane sparingly spiculate along margin of excava-
tion; ninth tergum with long, slender, apicolateral processes, the caudal mar-
gin between them with distinct cleft. Basistyle with heel and toe of the
foot-shaped ventral root well developed, dorsal root slender; dististyle curved
and moderately slender distally. Aedeagus with basal arch extending to 0.62 of
total length, basal arms curved and slender; distomedian process broad with
distally truncated tip. Parameres (Fig. 2g) each with midportion moderately
stout, definitely crooked in midportion; distal portion slender with 5-6 distal
fringing spines and fine-pointed tip.
Distribution.-Michigan to Quebec, south to Tennessee and Connecticut.
Type.-Holotype, female, Merrimacport, Massachusetts, 11-16 June 1954,
E. I. Coher, light trap (USNM 65719).
Discussion.-This species can be distinguished from C. parapiliferus by its
narrower eye separation, much shorter proboscis (P/H Ratio 0.70), shorter
third palpal segment, generally paler grayish pruinose mesonotum, the stouter

Vol. 57, No. 1

Wirth and Blanton: New Culicoides Species

distomedian process on the male aedeagus, and by the slender apicolateral
processes on the male ninth tergum.
Battle, F. B., and E. C. Turner, Jr. 1971. A systematic review of the genus
Culicoides (Diptera: Ceratopogonidae) of Virginia with a geographic
catalog of the species occurring in the eastern United States north of
Florida. Virginia Polytech. Inst. and State Univ. Res. Div. Bull.
44:1-129, fig.
Jamnback, H. 1965. The Culicoides of New York State (Diptera: Cera-
topogonidae). New York State Mus. and Sci. Serv. Bull. 399:1-154, fig.
Wirth, W. W., and A. A. Hubert. 1962. The species of Culicoides related to
piliferus Root and Hoffman in eastern North America (Diptera, Cera-
topogonidae). Ann. Ent. Soc. Amer. 55:182-195, fig.


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Department of Biology, University of Rochester
Rochester, New York 14627


Bituberochernes mumae, new genus and new species, is described on the
basis of a male collected from under bark in Dade County, Florida.

Through the courtesy of Dr. H. V. Weems, Jr., I have recently had the
opportunity to examine the pseudoscorpions of the Florida State Collection of
Arthropods. Several new and little known species are included, but one of the
most interesting is a chernetid with unusual palpal and pedal morphology,
which proved to represent an undescribed genus.

Bituberochernes, new genus
Diagnosis (based on male only): A genus of the family Chernetidae. Body
moderately stout, appendages rather long. All parts fairly heavily sclerotized,
brown; carapace and palps heavily granulate; legs, especially femora, scaly;
carapace with 2 shallow, indistinct transverse furrows; first and 11th tergites
entire, others partly divided or divided; 11th sternite entire, 4th-10th divided;
pleural membranes strongly rugose; most dorsal vestitural setae terminally
and laterally denticulate, those on ventral surfaces mostly acuminate; setae
of spiracular plates acuminate; 11th tergite and sternite each with 4 long,
acuminate tactile setae; setae of anal plates finely denticulate terminally;
genital opercula and internal genitalia generally typical of the Chernetidae.
Chelicera with 3 setae in flagellum; hand with 5 setae, b and sb terminally
denticulate, es long, acuminate; galea long, slender, with 1 small lateral ramus
and 3 or 4 small, terminal rami. Palps moderately slender and typical of the
family except for a distinct rounded, setiferous protuberance on medial side of
tibia and a small, conical, bare protuberance on medial side of chelal hand at
base of fingers; 50-60 "sense spots" on medial and ventral surfaces of chelal
hand; tibia longer than femur, chelal fingers slightly shorter than hand;
fingers with about 45 contiguous, marginal teeth, 1 internal and about 10
external accessory teeth; movable.chelal finger with well developed venedens
and venom duct reaching to level of trichobothrium t; fixed finger with short
venedens and very small, vestigial venom duct; trichobothrium t located

'Contribution No. 292, Bureau of Entomology, Division of Plant Industry, Florida Department
of Agriculture and Consumer Services, Gainesville, Florida 32602.
2Research Associate, Florida State Collection of Arthropods, Florida Department of Agriculture
and Consumer Services, Gainesville.

The Florida Entomologist

about one-third length of movable finger from distal end, st nearer to sb than
to t; fixed finger with ist at level of est, both in basal half of finger. All legs
monotarsate, moderately slender; each tarsus with an elevated slit sensillum
at basal fourth of segment; leg IV: tibia without a tactile seta, tarsus with a
very long tactile seta one-third length of segment from proximal end; leg I:
tibia and tarsus with irregular rows of very short, truncate (sensory?) setae
along ventral sides near distal ends.
Type species: Bituberochernes mumae, new species.
Etymology: The genus is named Bituberochernes with reference to the 2
protuberances on the palpal tibia and chela.
Remarks: Bituberochernes is unique among known chernetid pseudoscor-
pions in having a protuberance on both the tibia and the chela of the palp.
Mirochernes Beier, also known from Florida, has a large, anvil-shaped process
on the medial side of the chelal hand in the male but the tibia is normal. On the
other hand, Ancalochernes Beier from Mexico and Cordylochernes Beier from
Central and South America have a distinct protuberance on the palpal tibia,
but the chela is normal. Bituberochernes differs further from these and other
chernetid genera in the unusual relative length of the palpal tibia and the
unique short (sensory?) setae on the tibia and tarsus of leg I.

Bituberochernes mumae, new species
Fig. 1-4.
Material: Holotype male (WM 3110.01001) taken from under bark at
Matheson Hammock, Dade County, Florida, 12 September 1959 (M. H.
Diagnosis: Male easily distinguished from other chernetids by the pro-
tuberances on the palpal tibia and chela, the relative length of the palpal tibia
(greater than that of femur) and the unique, short (sensory?) setae on the tibia
and tarsus of leg I. (Female unknown).
Description of male: With the characteristics of the genus as outlined
above, and with the following particular features. Carapace longer than
broad; with 2 shallow, indistinct transverse furrows, 0.6 and 0.85 length of
carapace from anterior margin; surface granulate; 2 faint eyespots present;
about 80 short, dentate, vestitural setae, with 6 at anterior and 10 at posterior
margin. Tergites 1 and 11 entire, 2 partly divided, 3-10 divided; sternite 11
entire, 4-10 divided. Tergal chaetotaxy 10:10:10:12:13:14:13:14:
13:12:2T2T2T2:2; sternal chaetotaxy 52:(2) (3):(1)11(1):15:17:16:-
16:18:18:T3T4T3T:2; dorsal setae strongly dentate terminally and often
laterally (Fig. 1); ventral setae acuminate or finely denticulate; anterior
genital operculum with 6 long, heavy setae centrally, flanked by 46 smaller
ones; posterior operculum with 2 rows of 4 small setae just inside anterior
margin and 17 setae scattered on face; setae of spiracular plates acuminate;
setae of anal plates finely denticulate.
Chelicera one-third as long as carapace; hand with 5 setae, sb and b
terminally denticulate, es long, acuminate; flagellum of 3 setae, distal 1 den-
tate along margin; fingers normal; galea long, thin, with 1 small lateral and 3-4
small terminal rami; serrula exterior with 24-25 blades.
Palps relatively slender and not unusual except for the occurrence of 2
protuberances, 1 each on tibia and chelal hand, and the fact that tibia is

Vol. 57, No. 1

Muchmore: New Genus and Species of Pseudoscorpion 79

2 /


Fig. 1-4. Bituberochernes mumae, new genus and new species. 1-Examples
of setae from carapace and tergites. 2-Dorsal view of right palp showing
characteristic protuberances. 3-Lateral view of left chela. 4-Ventrolateral
view of tibia and tarsus of leg IV, showing short (sensory?) setae.

noticeably longer than femur (Fig. 2); the protuberance on medial side of tibia
is rounded and on its dorsal half bears 10 heavy, terminally dentate setae; the
protuberance on medial side of chelal hand near base of fingers is smaller,
conical and bare, but is flanked dorsally by a curved row of 5 heavy, acuminate
setae. Surfaces strongly granulate except chelal fingers; 50-60 conspicuous
"sensory spots" on medial and ventral surfaces of chelal hand. Trochanter
1.85, femur 2.8, tibia 2.65, and chela (without pedicel) 3.3 times as long as
broad; hand (without pedicel) 1.75 times as long as deep; movable finger 0.82
as long as hand. Each chelal finger with 46 contiguous, conical to quadrate
marginal teeth; fixed finger with 11 external and 1 internal accessory teeth,

80 The Florida Entomologist Vol. 57, No. 1

and movable finger with 9 external and no internal accessory teeth. Movable
finger with well developed venedens and venom duct, nodus ramosus at about
level of trichobothrium t; fixed finger with short venedens and very small,
vestigial venom duct. Trichobothria positioned as shown in Figs. 2 and 3; t
located about one-third length of movable finger from distal end, st nearer to
sb than to t; est and ist at same level, in basal half of fixed finger; left chela
(Fig. 3) with only 7 trichobothria on fixed finger (apparently isb missing), but
right chela with full complement of 8 (see Fig. 2).
Legs generally typical, moderately slender; leg IV with entire femur 2.65
and tibia 3.9 times as long as deep. Each tarsus with an elevated slit sensillum
at basal quarter. Leg I: tibia and tarsus unique in having irregular rows of very
short, truncated (sensory?) setae along ventral sides near distal ends (Fig. 4).
Leg IV: tibia without a tactile seta; tarsus with a very long tactile seta
one-third length of segment from proximal end.
Female: Unknown.
Measurements (mm): Body length 3.16. Carapace length 1.01. Chelicera
0.33 by 0.155. Palpal trochanter 0.52 by 0.28; femur 0.82 by 0.29; tibia 1.02 by
0.385; chela (without pedicel) 1.48 by 0.445; hand (without pedicel) 0.82 by
0.47; pedicel 0.095 long; movable finger 0.67 long. Leg I: basifemur 0.31 by 0.21;
telofemur 0.50 by 0.20; tibia 0.495 by 0.125; tarsus 0.415 by 0.075. Leg IV:
trochanter 0.325 by 0.185; entire femur 0.87 long; basifemur 0.35 by 0.245;
telofemur 0.69 by 0.33; tibia 0.66 by 0.17; tarsus 0.45 by 0.11.
Etymology: The species is named mumae for Dr. Martin H. Muma, out-
standing arachnologist, who collected the single known representative.
Remarks: The single male of Bituberochernes mumae was collected from
beneath bark along with 8 specimens of Paratemnus elongatus (Banks).
It is tempting to suggest that the protuberances on the palps and the short
setae on the first legs are modifications of the male for courtship or mating,
analogous to situations seen in other chernetid and cheliferid males. However,
in the absence of any knowledge of the morphology of the female or of the
behavior of the male, no answer to the questions can yet be given.

The assistance of Charlotte H. Alteri in preparing the illustrations is
gratefully acknowledged. This work was supported in part by National
Science Foundation Grant GB 37570.



Anthonomus flavus Boheman, a fruit-infesting weevil, was first collected
in the United States on 25 July 1972, at Hialeah, Florida by Carl Stegmaier. A.
flavus infests the fruit of the Barbados cherry shrub, Malpighia glabra L. One
to 20 larvae sometimes develop in a single fruit. The larvae pupate in a cavity
formed by their feeding. During the period 25 July 1972 through 16 July 1973,
473 adult weevils were swept from the foliage of Malpighia spp., 4 adults were
reared, and 144 larvae and 10 pupae were dissected from the fruit of M. glabra
in Dade County. A. flavus is known to occur in the United States only in Dade
County, Florida. Data on the life history, habits, hosts, and taxonomy of the
species are presented. The pupal stage is described for the first time.

The purpose of this paper is to present the first published record of
Anthonomus flavus Boheman from the United States and to contribute to the
knowledge of the life history, habits, hosts, and taxonomy of the species. On
25-27 July 1972 the senior author collected 21 adult specimens of a small
weevil from a Barbados cherry shrub, Malpighia glabra L., at Hialeah,
Florida. These specimens were submitted to Rose Ella Warner (Systematic
Entomology Laboratory, USDA) who determined them as Anthonomus
flavus Boheman and (Pers. comm., 4 Aug. 1972) stated that this constituted
a new record for the species from the United States. Previously A. flavus had
been known to occur in Puerto Rico; St. Croix, St. Thomas, and St. John
Islands; and-Guadeloupe.
Since relatively little is known about A. flavus, its discovery in Florida
afforded Stegmaier an excellent opportunity to pursue biological studies on
the species. The contribution of the junior author is mainly that of presenting
some preliminary information on the taxonomy of the species and describing
the pupal stage.

The first biological data recorded under the name "Anthonomus flavus
Boheman" were presented by Wolcott (1950) on the basis of observations
made in Puerto Rico. Wolcott described the injpry caused by the weevil on
fruit of Malpighia as being similar to that of the plum curculio, consisting of a

'Contribution No. 290, Bureau of Entomology, Division of Plant Industry, Florida Department
of Agriculture and Consumer Services, Gainesville, Florida 32601.
2Research Associate, Florida State Collection of Arthropods, Division of Plant Industry, Florida
Department of Agriculture and Consumer Services.
3Texas Agricultural Experiment Station, Department of Entomology, Texas A&M University,
College Station, Texas 77843.

The Florida Entomologist

crescentic scar on the skin of the fruit and puckering of the flesh. According to
Wolcott's account, the larva confines its feeding to one area and pupates in the
fruit near a seed. Wolcott later (1955) stated that on Malpighia punicifolia L.
(now considered by some to be a synonym of M. glabra) in Puerto Rico the
eggs are deposited either in the ovary of a flower or in tender young fruit. An
earlier record which probably refers to A. flavus also was made by Wolcott
(1936). He stated that "Anthonomus flavipes Boheman" had been reared from
the fruit of Malpighia glabra at Mayagiiez, Puerto Rico. We have been unable
to determine that a species by this name has been described in the genus.
Furthermore, judging from the host data given and the fact that Wolcott
stated that the type was from Guadeloupe (the type locality of A. flavus
Boheman), this appears likely to be an error in the spelling of the name;
Wolcott's statement probably refers to A. flavus.
Our first encounter with the immature stages of this weevil came on the
evening of 18 May 1973, when 22 larvae and 1 pupa were dissected from 6
malformed Barbados cherry fruit in Hialeah, Florida. Most of the larvae (Fig.
6) were found immediately beneath the skin of the fruit; however, some
individuals occurred within the flesh near the seeds. The single pupa was
found in a pupal chamber composed of seed fragments possibly cemented
together with fecal material on the exterior of a seed. One of the fruit
examined contained 10 larvae. It was noted also that the Caribbean fruitfly,
Anastrepha suspense (Loew), coexisted with some of the larvae of A. flavus.
On 19 May, 6 fruit were examined and found infested with 11 larvae of A.
flavus at the Stegmaier residence. Moreover, a single rotten fruit found on the
ground contained 4 live larvae. An infested fruit showing a crescentic scar of
the type mentioned by Wolcott (1950) is illustrated in Fig. 7. The infestations
cited above were found at the end of the fruiting period of M. glabra.
Mr. Robert J. Reasoner who resides in the neighborhood of 83rd Avenue
and S. W. 4th Street, Miami, collected 7 infested fruit of Malpighia glabra on
24 May; this fruit contained 39 larvae, 4 pupae, and a single general adult
which emerged while dissections were being made. A subsequent collection of
12 infested fruit taken by Mr. Reasoner from his neighborhood on 29 May
contained 61 larvae dissected from 10 fruit; however, 1 of the fruit was infested
with 20 larvae. Mr. Reasoner informed Stegmaier that the fruiting season for
Malpighia glabra was over at that time. The senior author tried to induce
pupation of larvae in the 2 remaining fruit collected by Mr. Reasoner and was
surprised to discover 4 pupae in 1 of the 3 seeds in the fruit.
Mr. Edward R. Bartley of Kendall, Florida, provided 20 fruit collected on
30 May 1973; however, upon examination these proved not to be infested. The
senior author and Mr. George Avery opened some 50 fruit at the Fairchild
Tropical Garden on 31 May 1973, and the findings were also negative. Sweep-
ing the foliage of 3 species of Malpighia on the same date proved to be
successful, as 92 adults were taken in this manner at the Fairchild Tropical
Garden. One plant known as Singapore Holly, Malpighia coccigera L., used
for ornamental purposes, about 14 in. high with spiny leaves was without fruit
but bore flowers and buds; 21 adult weevils were swept from this plant. It
should be noted here that Burke and Ahmad (1967), from their biological
studies on the genus Anthonomus, stated "Larvae of most species of
Anthonomus for which biological data are available develop either in the
flower buds, or in the flower heads or in a few cases as inquilines in various
types of galls. At least some of the few species which feed as larvae in fruits

Vol. 57, No. I

Stegmaier and Burke: Biology of Anthonomus flavus 83

may do so secondarily, as they are also known to develop in flower buds." A.
flavus probably develops in flower buds in Florida also, as it has been reported
to do so in Puerto Rico by Wolcott (1955).
On 31 May 1973, Dr. Robert Knight escorted the senior author through the
U. S. Plant Introduction Station (located 27 blocks south of the Fairchild
Tropical Garden) in an effort to establish other potential hosts for A. flavus
and distribution of the weevil. The search for the weevil was negative on this
date despite extensive sweeping of foliage of well established Malpighia
varieties and examinations of mature fruit. A return trip was made to the
"Station" on 7 June, and 96 fruit were collected from a variety of Malpighia
glabra, bearing the Plant Introduction No. 98866; this variety was imported
from Surinam, South America, in 1932. An examination of all of the fruit
present resulted in finding 3 larvae at the Station, and to date no further
records are available from this site.
Wolcott (1955) reported larvae of A. flavus feeding in the flower buds and
newly developing fruits of the West Indian cherry, M. punicifolia. Dr. Robert
Knight informed Stegmaier that "punicifolia" is considered by several sub-
tropical horticulturists to be a synonym of "glabra."
The single Barbados cherry shrub in Stegmaier's backyard is 20 years old,
and during the past 6 years it has been examined frequently to determine its
various insect associates. No weevils were recorded from the shrub until 25
May 1972, and even though R. E. Warner had indicated (Pers. comm., 4 Aug.
1972) that the weevil was new to North America, no further action was taken
until the senior author's wife brought him the aforementioned 6 malformed,
infested fruit on 18 May 1973. To date in Dade Co., Florida 473 adults have
been swept from Malpighia shrubs, 144 larvae and 10 pupae were dissected
from 199 fruit obtained from 3 localities, and 4 adults were reared from 2
Malpighia glabra, a glabrous shrub, grows to 10 ft. high (Bailey 1949). It is
native to northern South America northward to south Texas and occurs in
Florida and the West Indies.
No one knows for certain how A. flavus managed to become established in
Dade County. It is possible that some individual with a taste for exotic fruit
smuggled some infested Barbados cherry fruit from the Caribbean area into
Florida. Another possibility is that the weevil managed to reach Florida as a
hitchhiker aboard an aircraft. It is also quite possible that undetected weevil
infestations in varieties of Malpighia glabra, such as the B-17 variety, being
imported into Florida by nurseries, harbored A. flavus within the flower buds
or young fruit.
The preferred host for Anthonomus flavus probably is M. glabra; however,
more extensive research should be conducted by horticultural entomologists
stationed in south Florida to determine the extent of infestations on this and
other possible hosts.

TAXONOMIC RELATIONSHIPS-Anthonomus flavus was first described from
Guadeloupe by Boheman (1843). The species was not further treated
taxonomically until Hustache (1929) redescribed and keyed it in a publication
on curculionids of Guadeloupe. A. flavus is allied with a group of tropical
species referred to collectively by Champion (1903) as the A. venustus Group.



The Florida Entomologist Vol. 57, No. 1


Dates Number of Fruit Swept
Collected Host Examined Larvae Pupae Adults Site

25-VII-72 M. glabra 14 c
27-VII-72 ......... 7 c
18-V-73 ......... 6 22 1 c
19-V-73 ......... 6 11 17 c
20-V-73 ......... 20 c
21-V-73 ......... 49 c
22-V-73 ......... 14 c
24-V-73 ......... 7 39 4 d
26-V-73 ......... 16 c
29-V-73 ......... 12 62 3 d
31-V-73 M. coccigera L. 21 e
..... M. sp. (a) 25 33 e
........ M. glabra 25 38 e
3-VI-73 ......... 52 c
7-VI-73 M. glabra (b) 96 3 f
9-VI-73 ......... 26 c
10-VI-73 ......... 22 7 2 c
13-VI-73 ......... 16 c
19-VI-73 M. glabra 12 c
20-VI-73 ......... 39 c
25-VI-73 ......... 25 c
16-VII-73 ......... 41 c

TOTALS 199 144 10 473

a. Fairchild Tropical Garden. Ace. No. X-12-104. Believed to be a wild strain of Malpighia glabra.
b. U. S. Plant Introduction Station. Plant Introduction No. 98866, introduced from Surinam, S. A.,
in 1932. This introduction is a variety of Malpighia glabra.
c. C. Stegmaier's residence. 11335 N. W. 59th Avenue, Hialeah, Florida.
d. R. J. Reasoner's neighborhood. 83rd Avenue and S. W. 4th Street, Miami, Florida.
e. Fairchild Tropical Garden. 109th Street and Old Cutler Road.
f. U. S. Plant Introduction Station. 136th Street and Old Cutler Road, Miami, Florida.

Champion originally placed 5 species in this group, including Anthonomus
venustus Champion (Guatemala), Anthonomus cinerus Champion (Mexico),
Anthonomus melanostictus Champion (Panama), Anthonomus calvescens
Champion (Guatemala), and Anthonomus v-notatus Champion (Panama).
The latter 2 species obviously do not belong in the same taxonomic group as
the other 3 and are herein removed from the group. They are replaced in the A.
venustus Group by A. flqvus and Anthonomus tridens Fall which are as-
sociated with the group for the first time in the present paper. A. tridens was
described originally from Baja, California (Fall 1909), but it is now known to

Stegmaier and Burke: Biology of Anthonomus flavus 85

be more widely distributed in Mexico. Some species from the West Indies
probably fall into this group also. A careful taxonomic revision of the group is
needed to determine the relationships and status of the various species
The A. venustus Group is characterized by: the small size (2.2-3.3 mm);
relatively dense dorsal covering of small, elongate scales; color pattern of
elytra usually with an oblique light-colored line extending from humerus to
suture at middle forming a v-shaped pattern; profemora greatly enlarged,
maximum width about 1.6 X that of mesofemur; each profemur bearing 2 or 3
femoral teeth; protibiae strongly curved; middle and hind legs tending to be
testaceous in color and contrasting sharply with darker fore legs; eyes strongly
rounded; third elytral interval elevated at base.
It is also possible that the group may be further characterized on the basis
of host data. A. flavus develops in flower buds and fruit of Malpighia spp. A.
melanostictus has been collected on Malpighia sp. in Mexico, and an un-
described species of the group has been taken on Malpighia mexicana Juss. in
Mexico. Two species from St. Vincent which probably belong to this group
have been associated with Malpighia according to data from the (U. S.)
National Museum of Natural History provided by R. E. Warner (Pers. comm.,
24 July 1973). Although hosts are not known for the remaining species, it
seems safe to assume on the basis of their similarity to A. flavus and A.
melanostictus that these species also utilize plants of the family Mal-
pighiaceae as hosts. Other such well defined species groups in the genus
Anthonomus are confined to either a single plant genus or to closely related
genera as hosts.
In addition to A. flavus from Florida, 2 other species of the A. venustus
Group occur in the United States. A few specimens of an undetermined species
(near A. tridens Fall) have been collected in the vicinity of Brownsville, Texas.
Malpighia glabra occurs in the Brownsville area, but we have not had an
opportunity to collect on the plant there. A single specimen of an apparently
undescribed species has been examined from the Patagonia Mts., Santa Cruz
Co., Arizona. No species of Malpighia is known to occur in this area in
Arizona, but 2 other genera (Janusia and Aspicarpa) of Malpighiaceae are
found there (Kearney and Peebles 1969). A. flavus (Fig. 3, 4, 5) may be readily
separated from other species of the A. venustus Group examined by the fact
that it does not have a distinct metafemoral tooth.
Anthonomus unipustulatus Champion also develops in the fruit of Mal-
pighia spp. (Ahmad and Burke 1972; Berry 1959) in Mexico and Central
America. Ahmad and Burke (1972) cited collection data indicating that the
species also has been taken from the fruit of Malpighia glabra. The junior
author of the present paper has collected A. melanostictus and A. unipus-
tulatus from the same Malpighia tree in Mexico. However, the occurrence of
A. unipustulatus on Malpighia should not cause taxonomic confusion as it is
not closely related to any members of the A. venustus Group. A. unipustulatus
has the profemur only slightly larger than the mesofemur, and, in addition,
has a short stout rostrum and a single profemoral tooth.
DESCRIPTION OF PUPA-Terminology follows that of Burke (1968)
Length: 3.0-3.7 mm. (av. 3.2). Color: Whitish, turning darker with age;
prothoracic setae and process of 9th abdominal segment brown. Rostrum (Fig.
2): One pair of distirostral setae located just before middle of rostrum; each
borne on slight prominence; length of each seta equal to about 1/5 width of

The Florida Entomologist

Fig. 1 and 2. Pupa of Anthonomus flavus. (1) Dorsal view with
enlargement of laterotergal seta 2. (2) Ventral view.

rostrum; a pair of shorter, finer setae borne immediately distad of distirostrals.
One pair of straight to slightly curved basirostral setae, each borne on a small
tubercle, distance between setae equal to about 3/4 width of rostrum at base.
Head: A pair of frontal setae, separated by approximately same distance as
that separating basirostrals; stouter than basirostral setae. Supraorbital setae
present. Pronotum (Fig. 1): All pronotal setae associated with tubercles; setae
on anterior portion of pronotum stouter than those on posterior portion.
Three pairs of anterolateral setae, each borne on summit of low rounded to
subconical tubercle. Anteromedian setae each borne at apex on anterior face
of a tall conical to subconical tubercle; tubercles separated by distance
approximately equal to width of base of a tubercle. Posteromedian setae much
finer than anteromedians, located at middle to slightly behind middle of
pronotum, each borne on top of a low tubercle or on side of short, tooth-like
tubercle; tubercles separated by distance equal to about 3 X the width of one
of the tubercles at base. Three pairs of posterolateral setae, each of which is
borne at or near base of spinelike tubercle. Mesonotum: Three pairs of fine,
straight mesonotal setae, setae of 2 outer pairs each located at base of a
toothlike tubercle. Inner seta may be located either at base of a small

Vol. 57, No. 1

Stegmaier and Burke: Biology of Anthonomus flavus

Fig. 3, 4, 5. Adult of Anthonomus flavus collected at Miami, Fla. (3)
Lateral View. (4) Anterior portion of body showing enlarged profemora and
strongly curved protibiae. (5) Dorsal view showing color pattern of scales.

toothlike tubercle or on top of a small rounded one. Metanotum: Three pairs
of metanotal setae, like mesonotals except more widely separated. Abdomen:
Three pairs of discotergal setae on each of terga 18; setae fine, usually slightly
curved, each shorter than 1/2 length of tergum on which it is borne; DsT,
borne on summit of a small rounded to subconical tubercle; DsT, and DsT,
each borne near base of a spine-like tubercle except on tergum 8 where it is
located on summit of small tubercle; some tubercles with a small secondary
spine at apex. Laterotergal setae 1 short, each little if any longer than tubercle
on which it is borne; tubercles subconical, with a crown of 2 or more spines at
apex. Laterotergal seta 2 fine, attenuate, slightly curved; each borne on end of
a subconical or cylindrical tubercle bearing 3 short spines at apex (Fig. 1).
Segment 9 not bearing setae; terminated by a single process which is forked at
apex; extreme tip of each fork flattened. Laterosternal setae absent. Legs:
Hind femora each with a distinct projection on inner margin at apex; femoral
setae absent.

The Florida Entomologist

K'- r -

Fig. 6. Larvae of Anthonomus flavus feeding in the flesh of Malpighia
glabra fruit immediately under the skin. Fig. 7. Deformed Barbados cherry
fruit infested by larvae of Anthonomus flavus.

Material examined: Six pupae from Miami, Florida, 29 May 1973, C. E.
Stegmaier, Jr., ex. fruit of Malpighia glabra.
Diagnosis: The pupa of A. flavus is easily distinguished from pupae of the
approximately 50 species of the tribe Anthonomini for which this stage is
known. The prolonged inner apical angle of the metafemur and the peculiar
laterotergal tubercles (each bearing a crown of 2 or 3 teeth) separate A. flavus
from all other known pupae of the tribe. The single posterior process of the 9th
abdominal segment with the bifid apex is shared only with Anthonomus
albopilosus Dietz and Pseudanthonomus validus Dietz. A few other species
have a single process, but it is not forked at the apex.
LARVA-The larva of A. flavus was described and keyed by Ahmad and Burke
(1972), and little additional information on this developmental stage can be
offered here. The large number of larvae available during the present study did
make it possible to determine the number of larval instars. There are ap-
parently 3 instars (as in all other species of Anthonomus for which this
information is available) with head capsule widths being as follows: first
instar, 0.34-0.38 mm (9 specimens, av. 0.36 mm); second instar, 0.47 mm (1
specimen); third instar, 0.51-0.62 (40 specimens, av. 0.55 mm).

For reference purposes adults and larvae of Anthonomus flavus have been
deposited in the following collections: Systematic Entomology Laboratory, U.


Vol. 57, No. 1

Stegmaier and Burke: Biology of Anthonomus flavus 89

S. Department of Agriculture; Florida State Collection of Arthropods,
Division of Plant Industry, Gainesville; Florida A&M University; Plant Pro-
tection and Quarantine Programs, USDA, APHIS, Miami; University of
Florida, Subtropical Experiment Station, Homestead; U. S. Plant Introduc-
tion Station, Miami; Texas A&M University; University of California,
Riverside; Carnegie Museum, Section of Insects and Spiders, Pittsburgh.


Thanks are due the following persons who helped to make this paper
possible: R. E. Warner (Systematic Entomology Laboratory, USDA) for de-
termination of the weevil, Anthonomus flavus, and for various other assist-
ance; Dr. Robert Knight (research horticulturist, U. S. Plant Introduction
Station) for the translation of Wolcott's (1955) paper and for his assistance in
locating specimens of Malpighia species at the "Station"; Dr. John Popenoe
(Director, Fairchild Tropical Garden) for giving C. Stegmaier permission to
collect specimens of fruit and weevils in the "Garden"; George Avery (bo-
tanist, Fairchild Tropical Garden Research Center) for his help in locating
specimens of the various species of Malpighia; Robert J. Reasoner and Ed-
ward Bartley (Plant Protection and Quarantine Programs, USDA, APHIS,
Miami) for their collections of Barbados cherry fruit cited in this paper.


Ahmad, M., and H. R. Burke. 1972. Larvae of the weevil tribe Anthonomini
(Coleoptera: Curculionidae). Misc. Publ. Ent. Soc. Amer. 8(2):31-81.

Bailey, L. H. 1949. Manual of cultivated plants. Macmillan Co., New York.
1116 p.

Berry, P. A. 1959. Entomologia Econ6mica de El Salvador, Bol. Tec., no. 24,
Serv. Coop. Agricola., Minist. Agri. Ganaderia, El Salvador. 255 p.

Boheman, C. H. 1843. [description of new species]. In Schoenherr, Genera et
species curculionidum..., Vol. 7, pt. e, p. 237.

Burke, H. R., and M. Ahmad. 1967. Taxonomic status and relationships of
Coccotorus LeConte and Furcipus Desbrochers (Coleoptera: Cur-
culionidae). Ann. Ent. Soc. Amer. 60:1152-55.

Burke, H. R. 1968. Pupae of the weevil tribe Anthonomini (Coleoptera: Cur-
culionidae). Texas Agr. Exp. Sta. Tech. Monogr. 5. 92 p.

Champion, G. C. 1903. Rhynchophora, Curculionidae, In Biologia Centrali
Americana, Coleoptera IV (4):155-199.

Fall, H. C. 1909. New Coleoptera from the South-West. IV. Canad. Ent.

Hustache, A. 1929. Curculionides de la Guadeloupe. Faun. Col. Franc. 3:254.

The Florida Entomologist

Kearney, J. H., and R. H. Peebles. 1969. Arizona Flora (2nd ed). Univ. Calif.
Press, Berkeley. 1085 p.
Wolcott, G. N. 1936. "Insectae Borinquenses" A revised annotated checklist of
the insects of Puerto Rico. J. Agr. Univ. Puerto Rico. 20:627.
Wolcott, G. N. 1950. The insects of Puerto Rico. Coleoptera. J. Agr. Univ.
Puerto Rico. 32(2):225-416.
Wolcott, G. N. 1955. Entomologia Econ6mica Puertorriquefa. Bol. 125. Es-
tacion Exp. Agr. Univ. de Puerto Rico, Rio Piedras, Puerto Rico. 208 p.

AND INSECTS-(Note) While on the 1969 Alpha Helix Expedition to New
Guinea (N.S.F. supported through the Scripps Institution of Oceanography) I
encountered a number of luminescent mushrooms. Dramatic to a night visitor
to a rainforest, some are exceedingly conspicuous as they glow brightly against
pitch black. Since the luminescent chemical reaction uses energy, and natural
selection promotes efficiency, one is prompted to speculate on the adaptive
significance of this phenomenon. The fungal light may attract insects that
perform some service for the fungi. The fungivorous progeny of an attracted
insect might consume but a small portion of the fruiting body but at the same
time excrete chemicals that are essential for plant nutrition. (This hypothesis
does not seem as far fetched as the reality of a venus flytrap or sundew
capturing insects for their chemicals.) The attracted insects might disperse the
spores of the fungi. If spores matured after the luminescence had ceased, and
hence were not ready at the time of visitation, they might be carried away by
the maturing progeny of an oviposition visitant. Or, as in the relationship
between stinkhorn fungi and blow flies in European forests, an attracted
insect might eat nonripe spores that complete their maturation in its gut and
are later deposited elsewhere in the feces (W. Wickler, Mimicry, 1968, p. 155).
Even the weak hyphal luminescence of the nearctic Omphalotus illudens
might be attractive to soil or litter arthropods, where background light was
The interactions in these hypotheses can be considered communication in
the strict sense, since natural selection would enhance both signal and receiver
components in the context of information transfer. J. E. Lloyd, University of
Florida, Gainesville 32611.

Vol. 57, No. 1



Stored-Product Insects Research
and Development Laboratory, Agr. Res. Serv., USDA
Savannah, Georgia 31403


Ten krad of gamma irradiation to eggs and larvae of the slenderhorned
flour beetle, Gnathocerus maxillosus (F.), prevented development of adults.
Exposure of pupae to 5-100 krad allowed some emergence, but longevity was
greatly reduced except at 5 krad. The dose required to sterilize adults was
about the same as that for other species of stored-product tenebrionids: 20
krad was sterilizing to both sexes, and fecundity was greatly reduced by lesser
amounts. Also, adult longevity was significantly reduced since none survived
3 weeks after exposure to 10 krad. Adults and pupae of G. maxillosus would
require the same dose of irradiation for effective control as would most other
stored-product Coleoptera.

Most doses of gamma irradiation suggested for control of stored-product
insects have been based on results with only a few species, and the sensitivity
to irradiation of many economically important species has not been deter-
mined. However, if the method is to be used to control insects in stored
commodities, the dose must be sufficient to kill all species present at the time
of treatment. Therefore, the comparative radiosensitivity of all species com-
monly found infesting a given product must be determined. The radiosensi-
tivity of the slenderhorned flour beetle, Gnathocerus maxillosus (F.), has not
been reported previously though the USDA (Anon. 1962) lists it as a common
pest in flour, meal, and a variety of grains, particularly in the South.

The source of all test insects was the laboratory culture that is maintained
at 27 + 2 C and 60+ 5% RH with alternating 12-hr. light-12-hr. dark cycles. A
new culture was started twice a week, at which time all seeding adults were
removed. The test insects were reared on a medium of 47.5% wheat flour, 47.5%
finely ground cornmeal, and 5% brewer's yeast. Test eggs were obtained by
placing adults on finely sifted brewer's yeast and daily sifting off and
separating the adults and the eggs; those eggs that were not shrunken were
then placed individually in capsules dusted with yeast. Larvae were sorted
from precisely aged stock cultures and placed singly in capsules. Pupae were
obtained from cultures that were cleared of all pupae 6 days earlier; then the
pupae available were sexed and placed singly in capsules. Unmated adults
were obtained by isolating individual pupae in capsules until adults emerged,
and equal numbers of adults of each sex were tested.
During treatment and observation, the test insects were confined in clear
gelatin capsules (No. 000) with sufficient food for immediate needs; food was
added as the available supply was consumed. Each of the 3 replicates consisted
of 30 individual insects of each metamorphic stage, however, the treatments

The Florida Entomologist

were applied at random times on different days. At the time of irradiation, the
metamorphic stages were of the following ages: eggs, 3-4 days; larvae, 5 weeks;
pupae, 1-7 days; and adults, 3-5 days.
All stages were treated with each of 7 doses of irradiation: 0, 5, 10, 20, 30, 50,
and 100 krad. Treatment was administered in a '"Co irradiator with a source of
ca. 1.4 kCi at a dose rate of ca. 1.7 krad/min. All doses were verified with a
lithium fluoride thermoluminescence dosimetry system and found to be
within the + 5% limits of the dosimetry system.
During the period after treatment until they died, the insects were held at
controlled conditions of 27 + 2 C and 60 +5% RH and checked every 7 days.
Irradiated adults were paired with untreated unmated adults of the same age
in 2-dr vials half-filled with rearing medium. Fresh vials of food were provided
monthly. Progeny were counted as they emerged as adults.

Eggs.-The results for percent hatch obtained when fairly mature eggs
were treated are given in Table I. Although many eggs hatched after treat-
ment with 10-100 krad, the resulting larvae died within 2 weeks after exposure
to 30 krad and above and within 3 weeks after exposure to 10 and 20 krad.
Larvae that hatched from untreated eggs usually completed development


Dose % Egg to % Larva to % Pupa to adult
(krad) Larva Pupa Adult Pupa Adult Male Female

0 96.7 94.4 94.4 95.6 95.6 91.1 100
S9.8 3. 37.9 2.2 l.<<9 Y8.S 8&.
10 76.7 0 0 0 0 75.6 75.6
20 83.3 0 0 0 0 71.1 73.3
30 91.1 0 0 0 0 68.9 68.9
50 78.1 0 0 0 0 64.2 62.2
100 11.1 0 0 0 0 2.2 4.4

Larvae.-Mature G. maxillosus larvae were relatively radiosensitive:
although 95.6% of the control larvae became adults, only 50.0% of the larvae
treated with 5 krad and none treated with 10 krad were successful (Table 1);
no pupae were formed by larvae exposed to 10 krad or more. The pattern of
mortality of larvae that did not pupate is shown in Fig. 1. The greater the dose
of irradiation, the greater the rate of mortality. Untreated larvae pupated and
emerged within 2-3 weeks, but larvae treated with 10-100 krad all died within
4 weeks.

Vol. 57, No. 1

Brower: Radiosensitivity of Gnathocerus maxillosus


> DOSE (krad)

% "
% 0 50 .......

10 2 3 4 5 6

Fig. 1. Percentage survival of irradiated and unirradiated G. maxillosus
larvae (weeks posttreatment). Survival at the end of 5 weeks indicated that
these larvae pupated successfully.

Pupae.-The percentage of irradiated pupae that closed decreased as the
dose increased (Table 1), and very few adults emerged from pupae treated with
100 krad. No difference was apparent between the sexes in percentage eclosion
or in subsequent adult mortality so the data were combined. Mortality rates
of adults from treated pupae increased greatly as the dose was increased
(Table 2), and all adults from pupae treated with 10 krad were dead within 3
weeks. Even a dose of 5 krad increased mortality. At 30 weeks after treatment,
13.9% of the controls were dead compared with 27.5% of the insects treated
with 5 krad.

TABLE 2. Gnathocerus maxillosus: PERCENTAGE OF MORTALITY OF

Dose % mortality at indicated weeks after irradiation
(krad) 1 2 3 4 5 10 15 20 25 30

0 3.5 8.1 9.3 9.3 10.5 10.5 10.5 11.6 12.8 13.9
5 1.3 15.0 17.5 17.5 17.5 18.8 18.8 21.3 23.8 27.5
10 2.9 91.2 100
20 1.5 97.0 100
30 8.1 96.8 100
50 29.8 100
100 100

The Florida Entomologist

Adults.-The reproduction of males and females irradiated as adults is
shown in Table 3. Control pairs averaged 89.4% fertile, but fertility was
reduced to 20.4 and 2.6% in males and females, respectively, by treatment with
10 krad. No reproduction occurred if either member of a pair was exposed to 20
krad or more. Also, the number of progeny produced by each pair was greatly
reduced (Table 3). An average 73.2 adult progeny/pair was produced by un-
treated adults; the average number for irradiated adults was ca. 49 and 35
when males or females, respectively, were treated with 5 krad and 9.7 and 2.0
when they were treated with 10 krad.


Dose % Sterility of pairs Progeny per pair
Male Female from irradiated-
irradiated irradiated Male Female

0 10.6 10.6 73.2 73.2
5 14.3 26.8 48.8 35.4
10 79.6 97.4 9.7 2.0
20 100 100
30 100 100
50 100 100
100 100 100

The lifespan of both sexes of irradiated adults was shortened (Fig. 2). The
greater the dose, the sooner all insects died; mortality of both sexes was 100%
by 6 weeks when the exposure was 10 krad and by 3 weeks when it was 20 krad
and above. The mortality of adults treated with 5 krad was not greatly
different from that of the controls (Fig. 2). Shortening of the lifespan was
similar for both sexes so data for Fig. 2 were combined.

The radiosensitivity of G. maxillosus has not been reported previously, but
a brief report on that of G. cornutus (F.) does exist (Pesson 1963). The
radiosensitivity of the two species is similar. A dose of 16 krad appeared
adequate to control stored-product Coleoptera in bulk grain (Cornwell 1966),
but stored-product moths proved to be more resistant than beetles (Watters
1968). Therefore, the U. S. Food and Drug Administration (Anon. 1968)
approved a level of 20-50 krad for the control of all stored-product insects in
wheat and wheat flour. The present study shows that G. maxillosus falls
within the range of sensitivity of the other stored-product Coleoptera (Tilton
and Brower 1973). Therefore, when infested commodities are irradiated with a
dose near the minimum allowable (20 krad), G. maxillosus will be eliminated
within 3 weeks.

Vol. 57, No. I

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