A STUDY OF THE GEOLYCOSA PIKEI
COMPLEX IN THE SOUTHEASTERN
JOHN DAVID McCRONE
A T)IqSE 4--li PRFFNTTED TO TAU GRADUA'[E CouTN0L OF
THE UNIVERSITY OF FLORIDA
IN PAAnAL FULFILLMENT OF THE REQUIREIMFNTS FOR THE
M-GREE OF DOCTOR OF PH(LO-'OPHY
UNIVERSITY OF FLORIDA
I wish to thank Dr. H. K. Wallace, the chairman of my
graduate committee, for his initial guidance in selecting this
problem and his direction, encouragement and many valuable
suggestions throughout the course of the investigation.
I am also grateful to those who have served as members of
my graduate committee. These include: Doctors A. F. Carr, A. M.
Laessle, J. R. Redmond, T. J. Walker and H. M. Wallbrunn. Dr. M. J.
Fouquette gave valuable aid in the preparation of the illustrations.
Fellowships from the College of Arts and Sciences,
University of Florida and from the Southern Regional Fund provided
financial aid during the course of this investigation.
I am especially grateful to my wife and mother for their
encouragement and secretarial aid.
TABLE OF CONTENTS
ACKNOWLEDGE11ENTS ................................................ ii
LIST OF TABLES......................o ., .......................... iii
LIST OF ILLUSTRATIONS ........................................... iv
INTRODUCTION..............................v ..................... I
METHODS ......................................................... 3
SPECIES CRITERIA ................................................ 6
TAXONOMY ........................................................ 8
Geolycosa pikei (Marx) ..................................... 8
Geolycosa xera new species ................................. 9
Geolzcosa xera xera new subtpeciem ......................... 26
Geolycosa xera archboldi new subspecies .........,.......... 27
Geolycosa 2atellonigra Nallace ............................. 29
SEASONAL DISTRIBUT1ON ........................................... 46
G piE i ...................................................* 46
G xera .................................................... 47
. patellonigr6 ............................................ 47
Discussion .......................,..................... .... 53
POST-PLIOCENE HISTORY OF THE SOUTHEASTERN COASTAL PLAIN ......... 56
PRESENT DISTRIBUTION AND RABITAT RELATIONS ..,................... 65
CONCLtSIONS CONCERNING THE EVOLUTIONARY HISTORY OF THE COMPLEX.. 71
LITERAT MR CITED ...................,... ..............,........... 77
BIoGRAPHICAL, SKETCH .. .. .... ... ................ 80
LIST OF TABLES
1. Length of the carapace of female G. xera................... 17
2. Length of the epigynum of female G. xera................... 17
3. Length of the carapace of female G. patellonigra........... 38
4. Length of the epigynum of female G. patellonigra........... 41
5. Percentage of female G. patellonigra with light
patellae on legs III ind I1 ................................ 44
6. Observed seasonal population composition of G. pikei....... 46
7. Observed seasonal population composition of G. xera........ 47
8. Observed seasonal population composition of G.
patellonigra in Gilchrist, Clay, Putnam and Western
Volusia counties...................... .............. 48
9. Observed seasonal population composition of G.
patellonigra in Marion and Hillsborough counties........... 49
10. Observed seasonal population composition of G.
patellonigra in Levy, Alachua, Hernando and Sumter
counties................................ ................ ... 50
11. Observed seasonal population composition of G.
patellonigra in western Volusia, Brevard and Indian
River counties.......................................... ...53
12. Estimated duration and associated shorelines of the
Post-Pliocene Interglacial stages.......................... 64
LIST OF ILLUSTRATIONS
1. Comparison of the male palpal organs of G.
pikei, G. patellonigr and G. xera (holoTy-pe) ............. 13
2. Map showing the localities from which the samples of
the various populations of G. -,,(era were obtained .......... 16
3. Modified Dice-Leraas gymbols showing the variation
in the length of the carapace of femftle G. xera ........... 19
4. Symbols showing the variation in the length of the
epigynum of female G. xera ................................ 21
S. Frequency distributionx showing the variation in
color pattern on the ventr*l surface of legs I and
II in femwle G. xert ...................................... 24
6. Localities from which samples of the various
populations of G. patellonigra were obtained .............. 35
7.. Symbols showing the variation in the length of
the carapace of female G. patelloniEa .............. I ..... 37
8. Symbols shoving the variation in the ltngth of
the epigynum of femkle G. patellonigra .................... 40
9. Frequency distributions showing the viriation in
color pattern on the ventral surface of legs I tnd
11 in female G. patelloni .............................. 43
10. Map thowing the geographic variation in breeding
season in G. patelloniE a ................................. 52
11. Map Showing the approximate land areas of the
Okefenokee Sea ............................................ 58
12. )I*p Showing the approximate Itnd aro*4 of the
early Wicomico Sea ................... w ................... 61
13. Map showing the approximtte shoreline of the
Pamlico ...................... 63
14. Map shoving the distribution vf the mevg"rs of
the pilrei complex in Florida tnd Georgix .................. 67
In his revision of the burrowing wolf spider genus Geolycosa
Wallace (1942) described a new species, patellonigra. This species
was confined to Florida and inhabited inland, dune-like areas support-
ing sand-pine scrub or sandhill vegetation. Its morphology and habitat
preferences were similar to those of C. pikei (Marx), a species
inhabiting sandy beaches and inland sandhills along the Atlantic
seaboard from Massachusetts south to northern Georgia. These
similarities led Wallace to regard patellonigra as a southern derivative
of pikei. However, the exact relationship between pikei and patellonigra
was obscure because of the lack of male specimens from the Carolinas and
Georgia. The few female specimens from this area were arbitrarily
assigned to pikei. The populations included under the name patellonigra
showed a great deal of variation in morphology and seasonal distribution.
Because of this variation, Wallace felt that these populations might
constitute a complex rather than a single species.
This diversification in the southern part of the range is
striking in view of the relatively uniform topography of the southeastern
Coastal Plain. Several authors (Carr, 1940; Hubbell, 1954, 1956;
Highton, 1956; Neil, 1957) have noted a similar diversification in other
groups of animals which inhabit this area. They have sought an explana-
tion in the Post-Pliocene history of the area. MacNeil (1950) has
published a map of the Post-Pliocene shorelines of Florida and Georgia
which shows extensive insulation in this area. Recently, Laessle
(1958) was able to demonstrate that the distribution of sand-pine scrub
and sandhill vegetation can be closely correlated with the Post-Pliocene
shorelines plotted by MacNeil.
The present study is an attempt to clarify the taxonomic
status and seasonal distribution of the group of populations which
hereafter will be referred to as the pikei complex, and (in view of the
restriction of this complex to beaches, sandhills and sand-pine scrub)
to determine whether an explanation of its present status and distribu-
tion can be obtained by a consideration of the Post-Pliocene history of
The specimens used in this study were preserved in 70 per
cent or 95 per cent ethyl alcohol and were studied while under alcohol.
A data sheet was compiled for each adult specimen, and the following
information was recorded: 1) date of collection, 2) locality,
3) type of habitat, 4) a drawing of the ventral color pattern,
5) ecological and life history notes and 6) two measurements. The
measurements recorded for the females were the length of the carapace
and the length of the epigynum. The length of the carapace was
measured from the anterior margin of the posterior median eyes to
the posterior edge of the carapace. The length of the epigynum was
measured from the posterior end of the guide to the anterior end of
the furrow of the epigynum. Measurements recorded for the males were
the length of the carapace and the length of the cymbium.
The length of the carapace is the best indicator of body
size. The total body length varies widely because of fluctuations in
the size of the abdomen. These fluctuations are due to various factors
such as extent of ovarian development and the nutritional status of
During a preliminary study additional measurements were taken,
and several ratios were constructed from them. The measurements taken
were the width of the carapace, the width of epigynum, the height of
the carapace, the width of the cymbium and the lengths of the leg
segments. These measurements and ratios either showed no significant
geographic variation or were directly correlated with the length of
the carapace or the length of the epigynum.
The carapace measurements were made with a special measur-
ing microscope and are expressed in millimeter units. The genitalic
measurements were made with an ocular micrometer. Each micrometer
unit was equal to 0.033 mm. Since the readings were taken to the
nearest micrometer unit, the genitalic measurements are expressed in
micrometer units instead of millimeters to avoid the erroneous impression
that the genitalic measurements are accurate to one thousandth of a
Drawings of the ventral color pattern were made only from
freshly preserved specimens because long preservation results in the
loss of pigment in some areas. These drawings are stylized since only
areas of black pigmentation on the legs were recorded, and no attempt
was made to render the cuticle color or the shadings of gray on the
sternum and venter. Areas on the legs devoid of black pigment are
shown as being white instead of their normal buff color. Colors given
in the descriptions were determined by comparison with Maerz and Paul
(1930), under the artificial yellow light of an ordinary microscope
All of the specimens used in this study were collected either
by Dr. H. K. Wallace of the Biology Department of the University of
Florida or the author. All of the collection sites were visited
personally by the author so that field notes are available for all of
the locality records. The locality records given in the text are
accompanied by a catalog number. The initials HKW or JMcC before the
catalog number refer to the field notes of Dr. Wallace and the author,
It is difficult to collect males because they mature only at
certain seasons and have a short life span. For this reason, penulti-
mate males were brought into the laboratory and raised to maturity.
Comparison of these reared males with those collected in the wild
showed no apparent differences.
The taxonomic treatment of allopatric populations which are
separated by distributional gaps has been a source of controversy for
many years. Several yardsticks have been proposed to help determine,
in the absence of direct evidence of reproductive isolation, whether
these populations should be treated as species or subspecies
(Mayr et al., 1953). All of these yardsticks are based on an observed
correlation between morphological difference and reproductive isolation.
One approach is to compare the degree of difference between
two good systpatric species with the degree of difference existing
between the allopatric populations. Character displacement (Wilson
and Brownl956) would introduce a potential source of error into this
yardstick. According to this concept, when the ranges of two closely
related species partially overlap the differences between the two species
are accentuated in the area of sympatry. These differences tend to
disappear or lessen in the allopatric portions of the range. However,
this effect would lead to conservatism rather than excessive splitting.
Another approach is to compare the degree of difference
between the momt divergent, intergrading subspecies of a 'Widespread
species with the degree of difference between the allopatric populations.
Both of these comparisons are best made within the same genus.
In this study the first approach proved most fruitful. There
genus Geolycosa or in the family Lycosidae to warrant using the second
approach. A review of the morphological criteria used to differentiate
sympatric species in the genus Geolycosa and other lycosid genera showed
that the genitalia provide the most reliable taxonomic characters. The
female epigynum, however, is not as useful as the male palpal organ.
In his recent study of the lapidicina group of the genus Pardosa, Barnes
(1959) noted that the structure of the male palpal organ was the most
valuable character for the separation of species. The structure of the
female epigynum was very similar in all the species, and he had difficulty
in separating the females. Wallace (1942) in his study of the lenta
group of the genus Lycosa had similar difficulty separating the females
of a subgroup of three species even though the male palpal organ pro-
vided good separation.
In view of these findings, the degree of difference in the
morphology of the male palpal organ was considered the most important
species criterion in this investigation. A study of the epigynum and
ventral color pattern provided good separation of the females.
A consideration of the morphology, ecology and zoogeography
of the allopatric populations making up the pikei complex has resulted
in the recognition of three species and two subspecies. Two of the
species, G. pikei (Marx) and G. patellonigra Wallace, have been
previously described and their status is confirmed. G. xera and its
two subspecies G. xera xera and G. xera archboldi are described as new.
Geolycosa pikei (Harx)
New Records.-Georgia: Burke Co.: Keysville, Aug. 17, 1960,
Cat. JMcC 61-1, sandy field in turkey oak pen. males, 2 pen.
females; 6 mi. west of Swainsboro on U. S. 80, Aug. 17, 1960, Cat.
JMcC 61-2, turkey oak 7 pen. females. South Carolina: Lexington
Co.: Columbia, July 20, 1946, Cat. HKW 1230, turkey oak 1 female,
Geographic Distribution.-Atlantic Coastal Plain from northern
Georgia to Massachusetts and on adjacent islands.
Observations and Remarks.-The penultimate males collected on
August 17, 1960, at Keysville, Georgia,were brought into the laboratory
alive. Two of the twelve were successfully raised to maturity. Their
palpal organs were identical to those of males from the northern part
of the range of pikei and differed markedly from those of males from
all parts of the range of patellonigra.
An extensive search of the area lying between the southern
limit of pikei's range and the northern limit of patellonigra's
range (Figure 14) failed to produce any representatives of either
species. The absence of these spiders from this area is probably due
to the lack of suitable habitat. A large portion of the area is
occupied by the Okefenokee Swamp and great expanses of flatwoods.
The small patches of sandhill vegetation in the area are found only
along the banks, usually the northern, of the easterly flowing rivers.
These do not present the usual dune-like topography of the areas
inhabited by spiders of the pikei complex.
Geolycosa xera new species
Holotype.-Hale, from scrub eight miles north of Avon Park,
Polk Co., Florida, on U. S. 27, Nov. 21, 1960, Cat. JHcC 65;
allotype, a female with the same data: both will be deposited at the
American Museum of Natural History, New York.
Description of Holotype.-In alcohol Carapace uniform, no
median stripe; covered with silvery pubescence; central area beneath
pubescence near Windsor Tan; sides darker, near Leaf Mold. Dorsum of
abdomen covered with silvery pubescence; near Rose Beige beneath; no
markings; sides of abdomen black. Venter with a median dark band,
sides light. Sternum, coxae, endites and labium dusky; sternum lighter
than rest; femur of palpus dusky; patella and tibia light. Femora I-II,
patellae I-IV, tibia I, proximal half of tibia II, and proximal quarter
of tibia III-IV black beneath; femora III-IV dusky beneath; other
segments light. Chelicerae same color as sides of carapace.
Carapace longer than wide (6.1 mm./3.9 mm.), 3.0 mm. high;
width of head 3.3 mm. Posterior eye quadrangle wider than long
(2.0 mm. '1.3 mm.), median eyes the same size as laterals (0.5 mm.,/
0.5 mm.). Posterior median row wider than anterior row (1.5 mm.'
0.7 mm.); anterior row of eyes slightly procurved, eyes equally
spaced, medians larger than laterals (0.3 mm./0.2 mm.). Distance
from top of posterior median eyes to clypeus 1.0 mm. Palpal segments:
femur 1.9 mm., patella 0.9 mm., tibia 1.2 mm., tarsus and claws 2.0 mm.
Distance from posterior edge of epigynum to anterior end of furrow of
epigynum 0.5 mm. Legs 4123.
Femur Patella Tibia Metatarsus Tarsus Total
I 4.5 1.4 4.0 3.9 2.7 16.5
II 4.2 1.3 3.5 3.8 2.6 15.4
III 3.7 1.4 2.7 3.6 2.5 13.9
IV 4.8 1.4 4.4 4.9 3.0 18.5
Description of Allotype.-In alcohol Carapace uniform, no
median stripe; rubbed clear of most of whitish-gray pubescence; head
near Orange Chrome, rest of carapace near Burnt Sienna. Dorsum of
abdomen uniform, no markings, near Rose Beige; beset with numerous
black bristles; anterior part of abdomen surrounding pedicel black.
Venter without median dark band; same color as dorsum; beset with
numerous black bristles. Sternum, coxae, endites, and labium light;
all segments of palpus light. Femora I-II, patellae I-II, tibia I,
and proximal half of tibia II black beneath; other segments light.
Chelicerae near Burnt Sienna.
Carapace longer than wide (6.1 mm./3.9 mm.), 3.0 mm. high;
width of head 3.3 mm. Posterior eye quadrangle wider than long (2.0 mm./
1.3 mm.), median eyes the same size as laterals (0.5 mm./0.5 mm.).
Posterior median row wider than anterior row (1.5 mm./0.7 mm.); anterior
row of eyes slightly procurved, eyes equally spaced, medians larger
than laterals (0.3 mm./0.2 mm.). Distance from top of posterior median
eyes to clypeus 1.0 mm. Palpal segments: femur 1.9 mm., patella 0.9 mm.,
tibia 1.2 mm., tarsus and claws 2.0 mm. Distance from posterior edge
of epigynum to anterior end of furrow of epigynum 0.5 mm. Legs 4123.
Femur Patella Tibia Metatarsus Tarsus Total
I 3.9 1.4 3.1 2.8 2.1 13.3
II 3.5 1.4 2.7 2.4 2.0 12.0
III 3.1 1.3 2.2 2.8 2.2 11.6
IV 4.1 1.4 3.6 4.0 2.7 15.8
Diagnosis.-Figure 1 shows a comparison of the male palpal
organs of G. pikei, G. patellonigra and G. xera. These drawings were
made to scale by placing a squared grid in one ocular of a binocular
microscope. The shape of the median apophysis shows very little infra-
specific variation and is the most useful character for the separation
of these species.
Geographic Variation.-The structure and general conformation
of the male and female genitalia is uniform throughout the range. Al-
though only a distance of 77 miles separates the northern and southern
limits of the range, there is considerable geographic variation in the
length of the carapace, the length of the epigynum and the ventral color
pattern. The following analysis of variation is restricted to adult
females because of the small number of adult males available from each
locality. The carapace length and the ventral color pattern of the
males varies in the same manner as those of the females.
All of the available specimens were not used in this study.
In order to minimize the danger of lumping specimens from different
populations, a large series of specimens was collected from each of
several small areas throughout the range of the species. Each of these
series was designated a sample and assigned a number. Figure 2 shows
the areas from which the samples were drawn. The specific localities
included in the samples and the number of specimens taken from each
locality are listed below. The number of specimens are in parentheses.
Sample 1. Seminole Co.: Geneva (11). Volusia Co.:
Enterprise (2); 2.6 mi. E of Osteen (10);
Sample 2. Lake Co.: 0.5 mi. N of junction of State
Road 561 and State Road 448 on 561 (6).
Orange Co.i 5.5 mi. S of Apopka on State
Road 437 (2); 3.9 mi. SE of Apopka on U. S.
441 (1). Polk Co.: 17 mi. N of junction
of U. S. 27 and U. S. 92 on 27 (5).
Sample 3. Polk Co.: 8 mi. N of Avon Park on U. S.
Sample 4. Highlands Co.: 4 mi. E of Avon Park (9).
Sample 5. Highlands Co.: 2 mi. S of Avon Park on
U. S. 27 (17).
Sample 6. Highlands Co.:. 9.5 mi. N of junction of
U. S. 27 and State Road 621 on 27 (8);
junction of U. 5. '27 and U. S. 98 (4);
4.8 mi. S of junction of U. S. 27 and
U. S. 98 on 27 (7).
Sample 7. Highlands Co.: 1.2 mi. W of junction of
U. S. 27 and State Road 70 on 70 (25).
Figure 2. Localities from which the samples of the various
populations of G. xera were obtained. The outlined area represents
the total known distribution.
Figure 3 illustrates the trend of variation in the length of
the carapace throughout the range. With the exception of sample 4
there is a clinal decrease in length from north to south. A one-
tailed statistical comparison of the means of samples 3 and 4 was
made to determine whether the mean of sample 4 is significantly larger.
This gave a t-value of 2.048 (0.01
only nine specimens and is the smallest sample. Since the sample
variance is large, this sample may not represent a real break in the
dine. Figure 4 shows there is also a clinal decrease from north to
south in the length of the epigynum.
Table 1.-Length of carapace of female G. xera
Sample Sample 95% Confidence
number size Range Mean interval S. D.
1 27 5.7-8.8 6.9 6.6-7.2 0.719
2 15 5.3-8.7 6.7 6.1-7.3 1.034
3 45 4.5-8.0 6.0 5.7-6.3 0.874
4 9 5.1-8.4 6.7 5.8-7.6 1.221
5 17 4.8-7.5 5.8 5.4-6.2 0.828
6 19 4.6-6.5 5.6 5.3-5.9 0.550
7 25 4.2-7.0 5.3 5.0-5.6 0.777
Table 2.-Length of the epigynum of female G. xera
Sample Sample 955 Confidence
number size Range Mean interval 5. D.
1 27 14-18 16.1 15.7-16.5 1.100
2 15 14-18 16.5 15.7-17.3 1.356
3 45 13-17 14.8 14.5-15.1 0.975
4 9 14-16 15.0 14.3-15.7 0.866
5 17 14-16 14.9 14.5-15.3 0.749
6 19 12-16 14.3 13.7-14.9 1.149
7 25 13-18 14.3 14.0-14.6 0.781
Figure 3. Modified Dice-Leraas symbols (Simpson et al.,
1960) showing the variation in the length of the carapace of female
G. xera. The horizontal line represents the observed range, the open
rectangle ,4hows the standard deviation and the solid black, rectangle
indicates the 95 per cent confidence interval for the mean. The mean
is denoted by a vertical line and the number of specimens in each
Figure 4. Symbols showing the variation in the length of
the epigynum of female G. xera. For interpretation refer to Figure 3.
The numerical basis for these symbols is given in Table 2.
The most striking geographic variation involves the ventral
color pattern. Black pigmentation is mostly restricted to legs I and
II. Occasionally the femur of leg III is dusky and a few of the
specimens had black patellae on legs III and IV. Figure 5 shows the
trend of variation in the pattern of black pigmentation on legs I and
II. It can be seen that there is a sharp break in pattern between
samples 4 and 5. This sharp break is surprising since both of these
samples come from the town of Avon Park, and only two miles separate
the two localities. The area lying between these localities was in-
tensively searched, but no specimens were taken. Half of the specimens
in sample 5 appear to be intermediate between those in samples 4 and 6.
A single specimen in sample 7 falls within the range of sample 3.
The discontinuity in the trend of variation of the ventral
color pattern may be the result of one of two types of situations.
First, samples 1-4 and 5-7 may represent two populations which were
isolated from one another at one time. During this period of iso-
lation, the two populations would have had an opportunity to indepen-
dently evolve in response to the selection pressures in their respective
environments. Later when they came into contact they could have been
partially or completely reproductively isolated. A second possibility
is that the abrupt change in color pattern may not represent a change
from one to another genetically isolated population. Instead it may
only be the result of an abrupt change from one type of environment or
habitat to another. Thus this discontinuity does not necessarily in-
dicate absence or reduction of gene flow between the two populations.
Figure 5. Frequency distributions showing the variation
in color pattern on the ventral surface of legs I and II in female
G. xera. The digits above the bars denote the number of individuals
in eac class.
Such a sudden change in environment or habitat is not
apparent in this area. The first situation seems more likely in view
of the geological history of the area. The central part of each of
the areas occupied by these two populations represents an old
Pleistocene island. These islands were separated from each other
for a period of approximately 200,000 years during the Aftonian In-
tergalcial stage, when strong currents of the Okefenokee Sea passed
between them. This situation will be discussed more fully in the
section of this paper dealing with the evolutionary history of the
In the absence of genetic information, the taxonomic treat-
ment of these two populations presents a difficult problem. Although
the ventral color pattern on legs I and II provides almost 100 per
cent separation of samples 1, 2, 3 and 4 from samples 5, 6 and 7, the
structure of the male and female genitalia is uniform throughout the
range. The variation in the length of the female epigynum is clinal
and does not allow for separation. In the discussion of species
criteria, the importance of the degree of difference of the genitalia
in determining specific status was stressed. Using this criterion it
is apparent that the northern and southern populations must be in-
cluded under one specific name. However, the variation in the ventral
color pattern considered in conjunction with the geological history of
the area would suggest that there is little gene flow between the two
populations. Therefore, these two populations have been named as sub-
species on the basis of the difference in the ventral color pattern on
legs I and II.
Geolycosa xera xera new subspecies
Remarks.-This is the nominate subspecies. A description of
the holotype and allotype are given above.
Geographic Distribution.-Central Florida South Volusia Co.,
Seminole Co., Orange Co., Lake Co., Polk Co. and northern Highlands
Co. (Figure 14)
Records.-Florida: Highlands Co.: 4 miles east of Avon Park,
Nov. 21, 1960, Cat. JMcC 66-1, road shoulders through scrub 9 females.
Lake Co.: 0.5 miles north of junction of State Road 561 and State Road
448 on 561, Dec. 30, 1959, Cat. JMcC 31, turkey oak 6 females, 1 imm.
Orange Co.: 5.5 miles south of Apopka on State Road 437, Dec. 30,
1959, Cat. JMcC 39, scrub 2 females, 1 imm.; 2.7 miles south of
Orlovista, Oct. 24, 1957, Cat. HKW 1923, scrub 11 females, 1 imm.;
3.9 mi. southeast of Apopka on U. S. 441, Mar. 1, 1939, Cat. HKW 1085,
turkey oak 1 female; 3.3 miles northwest of Apopka on U. S. 441,
Mar. 2, 1939, Cat. HKW 1087, scrub 1 female. Polk Co.: 8 mi. north
of Avon Park on U. S. 27, Oct. 27, 1957, Cat. HKW 1939, scrub 3
females; Dec. 31, 1959, Cat. JMcC 28, 11 females, imm.; Sept. 28, 1960,
Cat. JMcC 62-3, 14 pen. males, 8 pen. females; Nov. 21, 1960, Cat. JMcC
65, 4 males, 25 females; junction of U. S. 27 and State Road 640,
Dec. 31, 1959, Cat. JMcC 30, scrub 4 females, imm.; 20.6 mi. south of
Haines City on U. S. 27, Aug. 30, 1957, Cat. HKW 1913, scrub 2 imm.;
17 mi. north of junction of U. S. 27 and U. S. 92 on 27, Dec. 30, 1959,
Cat. JMcC 35, turkey oak 5 females, 2 imm. Seminole Co.: Geneva,
Dec. 30, 1959, Cat. JMcC 35, turkey oak 2 females. Volusia Co.:
2.6 mi. east of Osteen, Dec. 29, 1959, Cat. JMcC 29, scrub 8 females,
imm.; Enterprise, Dec. 29, 1959, Cat. JMcC 36, scrub 2 females;
DeBary, Apr. 15,1960, Cat. JMcC 60-2, scrub 4 females, 2 imm.; Sept.
28, 1960, Cat. JMcC 62-2, 1 pen. male.
Geolycosa xera archboldi new subspecies
Holotype.-Male, from scrub at junction of State Road 70
and State Road 17, Highlands Co., Fla., Oct. 25, 1957, Cat. HKW 1928;
allotype, a female with the same data: both will be deposited in the
American Museum of Natural History, New York.
Description of Holotype.-In alcohol Carapace uniform, no
median stripe; covered with silvery pubescence; beneath pubescence
central area near Windsor Tan; sides darker, near Burnt Sienna. Dorsum
of abdomen covered with thick silvery pubescence, no markings; sides of
abdomen black. Venter dusky. Sternum, coxae, endites and labium light;
all segments of palpus light. Proximal half of tibia I and proximal
third of tibia II black beneath; femora I-II dusky beneath; other
segments light. Chelicerae near Burnt Sienna.
Carapace longer than wide (5.4 mm./3.7 mm.), 2.3 mm. high;
width of head 2.6 mm. Posterior eye quadrangle wider than long
(1.7 mm./l.3 mm.), eyes of median row larger than those of posterior
(0.7 mm./9.5 mm.); median row wider than anterior row (1.3 mm./0.7 mm.).
Anterior row of eyes slightly procurved, eyes evenly spaced, medians
larger than laterals (0.3 mm./).2 mm.). Distance from top of posterior
median eyes to clypeus 1.3 mm. Palpal segments: femur 2.0 mm., patella
0.6 mm., tibia 1.1 mm., cymbium 1.6 mm. Legs 4123.
Femur Patella Tibia Metatorsus Tarsus Total
1 4.8 1.4 4.5 4.2 3.0 17.9
II 4.2 1.4 3,9 4.2 3.o 16.7
111 4.0 1.3 3.3 4.2 2.9 15.7
IV 5.0 1.5 4.8 5.7 3.3 20,3
Description of Allotype,-In alcohol Carapace uniform, no
median stripe; covered lightly with whitish-gray pubescence; near
Orange Chrome beneath pubescence. Dorsum of abdomen uniform, no mark-
ings; color near Rose Beige; beset with numerous black bristles;
anterior part of abdomen surrounding pedicel black. Venter dusky;
beset with numerous black bristles. Sternum, endites and labium
dusky; coxae light; femur of palpus dusky; all other segments light.
Proximal third of tibia I and proximal fifth of tibia II black beneath;
femur I dusky beneath; all other segments light. Chelicerae same color
Carapace longer than wide (6.0 mm./4.0 mm.), 2.5 mum. high;
width of head 3.2 mm. Posterior eye quadrangle wider than long (2.0
mm./1.5 mm.), median eyes larger than laterals (0.6 mm./0.5 wm.). pos-
terior median eyes to clypeus 1.3 mm. Palpal segments: femur 2.2 mm.,
Patella 0.9 mm., tibia 1.2 mm., tarsus and claws 1.9 Tn. Distance from
posterior edge of epigynum to anterior end of furrow of epigynum 0.6
mm. Legs 4123,
Femur Patella Tibia Metatarsus Tarsus Total
1 4.1 1.7 3.3 3.0 2.2 14.3
II 3.9 1.8 2.8 2.9 2.1 13.5
Geographic Distribution.-Highlands Co.
Records.-Florida: Highlands Co.: 2 mi. south of Avon Park
on U. S. 27, Nov. 21, 1960, Cat. JMcC 66-2, scrub 2 males, 17 females,
2 imm.; 4.8 mi. south of junction of U. 5. 27 and U. 5. 98 on 27,
Nov. 21, 1960, Cat. JMcC 66-3, scrub 3 females; Oct. 27, 1957,
Cat. HKW 1936, 11 females, 1 imm.; Archbold Biological Station,
Oct. 25, 1957, Cat. }IKW 1927, scrub 26 females, 2 imm.; junction of
State Road 70 and State Road 17, Oct. 25, 1957, Cat. HIW 1928, scrub -
1 male, 42 females, 3 pen. males, 13 imm.; Aug. 28, 1957, Cat. HKW 1907,
3 pen, males, 2 pen. females; 1.2 mi. west of junction of State Road 70
and State Road 17 on 70, Dec. 31, 1959, Cat. JIcC 32, scrub 3 females;
6.1 mi. north of junction of U. S. 27 and State Road 621 on 27, Jan. 1,
1960, Cat. JMcC 33, scrub 4 females; 9.5 mi. north of junction of U. 5.
27 and State Road 621 on 27, Jan. 1, 1960, Cat. JMcC 40, mixed turkey
oak and scrub 8 females; 4 mi. southeast of Archbold Biological Station,
Aug. 29, 1957, Cat. HKW 1912, scrub 4 females, 5 pen. females, 5 pen.
males; junction of U. S. 27 and U. S. 98, Oct. 27, 1957, Cat. HKW 1937,
scrub 4 females, 1 male; 10 mi. north of junction of U. S. 27 and
U. S. 98 on 27, Oct. 27, 1957, Cat. HKW 1938, scrub 5 females.
Geolycosa patellonigra Wallace
New Records.-Florida: Alachua Co.: 2 mi. west of Archer on
State Road 24, Mar. 29, 1946, Cat. HhKW 1179, sandy field in turkey oak -
1 male, 8 females, 2 imm.; May 25, 1949, Cat. HKW 1316, 5 females, 3
pen. females; Dec. 7, 1958, Cat. JMcC 4, 2 females, 3 pen. males, 2 pen.
females. Brevard Co.; 4 mi. north of Cocoa on U. S. 1, Feb. 5, 1960Y
Cat. JMcC 53, sandy field in scrub 9 females, 1 pen. male (matured
on Feb. 22, 1960); liar. 210, 1961, Cat. JMcC 68, 2 females. Broward
Co.: Fort Lauderdale, Feb. 4, 1960, Cat. JMcC 50, scrub 7 females,
I pen. male. Citrus Co.: 3 mi. east of Holder on State Road 491,
Oct. 18$ 1957, Cat. Hh-W 1916, scrub 2 females. Clay Co.: Lake
Brooklyn, Dec. 13, 1958, Cat. J'McC 5, turkey oak 4 females; Aug. 18,
1959, Cat. JMcC 23-1, 1 pen. male; Goldhead State Park, June 8, 1959,
Cat. JMCC 18 turkey oak 5 pen. females, 9 imm.; Nov. 15, 1960, Cat.
JMcC 64-2, 1 male; 15 females; 0.4 mi. west of Putnam Clay line on
State Road 214, Aug. 18, 1959, Cat. JMcC 23-2, sandy field in turkey
oak 5 pen. males, 9 pen. females; Nov. 15, 1959, Cat. JIIcC 26, 1 male,
11 females; Nov. 15, 1960, Cat. JMcC 64-1, 1 male, 10 females. Gilchrist
Co.; 6.2 miles west of Newherry on State Road 26, Oct, 20, 1946, Cat.
HKW 1236, turkey oaR 9 females, 2 pen. males, 5 pen. females, 2 imm.;
Oct. 17, 1954, Cat. HKW 1856 11 females, 4 pen. males, 5 imm.; Apr. 5,
1959, Cat. JIIcC 151 2 females, 10 imm.; July 8, 1959, Cat. a1cc 21, 1
pen. male, (matured Aug. 21, 1959), 1 pen. female; Oct. 3, 1959, Cat.
JITcC 24Y 2 males, 12 females, 2 pen. males, 3 imm,; liar. 19, 1960,
Cat. 57-1, 5 females, 3 imm.; 11 mi. north of Bell on State Road 129,
Nov. 221 1959, Cat. JMcC 27-2, road shoulders through turkey oak 2
foaales. Hernando Co.: 'Weeki Wachee Springs, Mar. 23, 1947, Cat. HRW
1249, road shoulder through scrub 7 imm.; Oct. 18, 1957, Cat. HKW
19191 1 female, 3 imm.; Jan, 2, 1960, Cat. JMcC 38, 6 females, 3 pen.
female5i 5ept. 28, 1960, Cat. 62-41 8 females, 2 pen, males (both of
these matured on Mov. 30, 1960); Apr. 11, 1961, Cat, JMcC 69-3, 7
females (3 with young), 1 pen. male, 2 imm. Hillsborough Co.: 4 miles
south of Boyette, June 20, 1959, Cat. JMcC 19-3, road shoulders through
scrub 6 females; Sept. 28, 1960, Cat. JMcC 62-5, 8 females (1 with
egg sac); Apr. 11, 1961, Cat. JMcC 69, 5 females, 1 pen male, 8 pen.
females. Indian River Co.: 6 mi. south of Vero Beach on U. S. 1, Feb.
5, 1960, Cat. JMcC 54, scrub 2 females, 1 pen. male (matured Feb. 17,
1960); 0.5 mi. north of Sebastian on U. S. 1, Mar. 20, 1961, Cat. JMcC
68, scrub 18 females (1 with young), 6 imm. Levy Co.: 5 mi. west of
Archer on State Road 24, Mar. 2, 1946, Cat. HKW 1174, road shoulders
through turkey oak 5 females, 5 pen. males, 5 pen, females; Mar. 29,
1946, Cat. HK1 1180, 3 males, 30 females, 1 pen. male, 10 imm.; Apr. 8,
1951, Cat. HKW 1377, 2 females (1 with egg sac, 1 with young); Apr. 10,
1959, Cat. JMcC 17, 8 females, 4 pen. females, 2 imm.; 8 mi. west of
Archer on State Road 24, Feb. 1, 1959, Cat. JMcC 8, turkey oak 2
females, 2 pen. males, 1 pen. female, 5 imm.; Apr. 6, 1959, Cat. JMcC
16, 1 male, 3 females, 1 pen. female, 6 imm.; 8 mi. southwest of Wil-
liston on State Road 335, Apr. 4, 1959, Cat. JMcC 14, road shoulders
and sandy field in turkey oak 1 male, 10 females, 18 imm.; Oct. 18,
1959, Cat. JMcC 25, 4 males, 3 females. Marion Co.: 1 mi. east of
Eureka on State Road 316, Mar. 21, 1959, Cat. JMcC 12-2, scrub 3 pen.
females; 4 mi. east of Eureka on State Road 316, Mar. 21, 1959, Cat.
JMcC 12-3, ecotone between scrub and turkey oak 1 male, 1 female, 3
pen. females; Juniper Springs, Aug. 14, 1959, Cat. JMcC 22, road shoul-
der through scrub 6 females (3 with young). Martin Co.: 4 mi. north
of Jupiter on U. S. 1, Feb. 4, 1960, Cat. JMcC 52, scrub 1 female, 3
pen. males (1 matured Feb. 28, another Mar. 6), 2 pen. females. Palm
Beach: Delray Beach, Feb. 4, 1960, Cat. JMcC 51, scrub 7 females,
3 pen. males, 1 pen. female. Pinellas Co.: St. Petersburg, Jan. 31,
1960, Cat. JMcC 46, scrub 2 females, 2 pen. females. Putnam Co.:
21.4 mi. east of Gainesville on State Road 20, Mar. 3, 1946, Cat. HKW
1177, turkey oak 2 males, 26 females, 9 imm.; 4 mi. north of Orange
Springs on State Road 21, Mar. 8, 1959, Cat. JMcC 11, turkey oak 3
females, 6 imm.; Interlachen, Mar. 3, 1946, Cat. HKW 1178, ceratiola
covered field 3 females, 5 imm.; Oct. 23, 1954, Cat. HKW 1857, 3
females; Nov. 15, 1960, Cat. J~cC 63, 2 males, 10 females. St. Lucie
Co.: Nigger Jim Scrub, Oct. 26, 1957, Cat. HKW 1930, scrub 4 females.
Sumter Co.: Sumterville, June 19, 1959, Cat. JMcC 19-1, road shoulders
through turkey oak 3 females, 2 pen. females; July 4, 1959, Cat. JMcC
20, 4 females (2 with young), 1 pen. male (matured July 15); Apr. 10,
1960, Cat. JMcC 59, 1 imm.; Apr. 11, 1961, Cat. JMcC 69, 7 females, 4
imm. Volusia Co.t DeLeon Springs, Dec. 29, 1959, Cat. J~cC 41, road
shoulders through scrub I female, 3 imm.; Apr. 15, 1960, Cat. J~cC
621 8 females, 3 pen. males (I matured Nov. 7); Daytona Beach Airport,
Feb, 5, 1960, Cat. JIcC 55, scrub 10 females, 2 pen. males (both
matured Feb. 17), 1 imm.; Mar. 20, 1961, Cat. JMcC 68, 14 females (2
with young), 8 imm.
Geographic Distribution.-Florida North Central, East Coast
and West Coast (Figure 14).
Geographic Variation.-The method of analysis of the geographic
variation in Eatellonigra is the same as that used for xera. Again the
study i restricted to adult females. The structure and general con-
formation of the male and female genitalia it uniform throughout the
range, but considerable geographic variation was found in the length
of the carapace, length of the epigynum and various aspects of the
ventral color pattern. The ventral color pattern and the length of the
carapace of the males vary in the same manner as those of the females.
Figure 6 shows the areas from which the samples were taken.
Sample 1. Hillsborough Co.: 4 mi. S of Boyette (18).
Sample 2. Hernando Co.: Weeki Wachee Springs (19).
Sample 3. Sumter Co.: Sumterville (16).
Sample 4. Levy Co.: 6 mi. W of Archer on State Road
24 (13); 8 mi. W of Archer on State Road
24 (10); 9 mi. W of Williston on State Road
335 (9). Alachua Co.z 2 mi. W of Archer
on State Road 24 (2).
Sample 5. Gilchrist Co.: 6.2 mi. W of Newberry on
State Road 26 (36); 11 mi. N of Bell on
State Road 129 (2).
Sample 6. Clay Co.s Goldhead State Park (15).
Sample 7. Clay Co.s 0.4 mi. W of Putnam-Clay county
line on S 214 (21).
Sample 8. Putnam Co.: Interlachen on State Road 20 (14).
Sample 9. Marion Co.: Ocala National Forest (32).
Sample 10. Volusia Co.i De Leon Springs (11).
Sample 11. Volusia Co.: Daytona Beach airport (22).
Sample 12. Brevard Co.: 4 mi. N of Cocoa on U. S. 1 (11).
Sample 13. Indian River Co.: 0.5 mi. N of Sebastian on
U. S. 1 (17); 6 mi. S of Vero Beach on U. S. 1
Sample 14. Broward Co.: Ft. Lauderdale (6); Delray Beach
Figure 7 illustrates the trend of variation in the length of
Figure 6. Localities from ,Aiich the samples of the various
populations of G. patelloniZra were obtained. The outlined area
repre8ents the total known distributional range.
of the carapace of
refer to Figure 3.
in Table 3.
Symbols showing the variation in the length
female G. patellonigra. For interpretation
The numerical basis for these symbols is given
S I I I I l I
5 6 7 8 9 10 1 I
MIL L IMETE R S
the carapace throughout the range. In many cases the interpopulation
differences in carapace length are quite pronounced. For example,
there is no overlap in the observed ranges of samples 6 and 14. How-
ever, there are no discernible clinal trends in this character, and
the variation is chaotic.
Table 3.-Length of the carapace of female G. patellonigra
Sample Sample 95% Confidence
number size Range Mean interval S. D.
1 18 7.4- 9.6 8.5 8.2- 8.8 0.619
2 19 6.6-10.1 8.9 8.4- 9.4 0.074
3 16 6.9- 8.6 7.8 7.5- 8.1 0.520
4 34 5.8-10.3 7.7 7.4- 8.0 0.939
5 38 6.6-10.0 8.6 8.3- 8.9 0.912
6 15 7.7- 9.7 8.7 8.4- 9.0 0.612
7 21 5.4- 8.5 7.1 6.6- 7.6 0.962
8 14 6.4- 9.2 7.9 7.4- 8.4 0.865
9 32 7.2-11.0 9.6 9.2-10.0 0.983
10 11 6.8-10.9 8.9 7.9- 9.9 1.453
11 22 5.5- 8.5 6.4 6.0- 6.8 0.897
12 11 5.3- 7.5 6.4 5.9- 6.9 0.758
13 19 6.6- 9.2 7.9 7.6- 8.2 0.657
14 12 5.8- 7.6 6.7 6.4- 7.0 0.523
Figure 8 shows the trend of variation in the length of the
epigynum. There are no definite clinal trends, but with the exception
of sample 2 the populations in the southern parts of the range tend to
have shorter epigyna. In xera, there was a close correlation between
the trend of variation in the length of the carapace and the length of
the epigynum. In patellonigra, no such correlation is evident. For
example, the mean length of the carapace in samples 1 and 5 is similar,
but the mean length of the epigynum is very different.
Figure 8. Symbols showing the variation in the length of
the epigynum of female G. patellonigra. For interpretation refer
to Figure 3. The numerical basis for these symbols is given in
8 (14_.ELZ i
I I I I
15 16 17 18 19 20 21 22 23 24 25 26
Table 4.-Length of the epigynum of female G. patellonigra
Sample Sample 95% Confidence
number size Range Mean interval S. D.
1 18 18-21 19.4 18.9-19.9 0.923
2 19 20-26 22.1 21.4-22.8 1.487
3 16 17-22 19.2 18.4-20.0 1.470
4 34 17-24 20.6 20.0-21.2 1.689
5 38 19-25 21.6 21.1-22.1 1.411
6 15 20-24 21.5 20.9-22.1 1.127
7 21 18-23 20.8 20.2-21.4 1.364
8 14 20-25 21.5 20.8-22.2 1.225
9 32 19-25 22.0 21.4-22.6 1.533
10 11 17-22 20.5 19.6-21.4 1.371
11 22 17-22 19.0 18.4-19.6 1.273
12 11 18-21 19.4 18.8-20.0 0.925
13 19 17-22 19.9 19.2-20.6 1.353
14 12 16-21 18.5 17.6-19.4 1.382
Patellonigra, like xera, shows considerable variation in the
ventral color pattern on legs I and II. Figure 9 illustrates this
variation. Samples 11-14 reveal that on the East Coast, from Daytona
Beach south to Ft. Lauderdale, there is a clinal change in the distribu-
tion of black pigment on femora I and II. A similar dine on the West
Coast would probably be demonstrated if specimens were available from
the area lying between samples 1 and 2. It is interesting that the
ventral color pattern on legs I and II is identical in samples 1 and
14. Although these samples were taken at different latitudes, they both
represent the southernmost, known population on each coast.
Samples 3 and 10 represent populations that have the closest
contact with the range of xera. Samples 11 and 12 were also taken from
areas that are spatially close to the range of xera, but the intervening
terrain is ecologically unsuitable for both species. Both samples 3
Figure 9. Frequency distributions showing the variation
in color pattern on the ventral surface of legs I and 1I in female
G. patellonigra. The digits above the bars denote the number of
individuas -n each class.
I I 3
3 4 3
and 10, show a greater variability in color pattern than the rest of
the samples. This variability is in the direction of, but does not
overlap the color patterns of the specimens of xera taken near these
areas. This increased variability may be the result of secondary
intergradation and the introgression of xera color pattern genes into
patellonigra. The palpal organs of the few male specimens from these
areas show the typical patellonigra type of structure.
As the name patellonigra implies, most of the specimens have
black pigmentation on the ventral surface of their patellae. However,
some of the samples contained individuals with light patellae on legs
III and IV. The percentage of individuals in each sample with light
patellae is given in Table 5.
Table 5.-Percentage of female G. patellonigra
with light patellae on leg and IV
Sample Sample Number of individuals Percentage of individuals
number size with light patellae with light patellae
1 18 0 0
2 19 0 0
3 16 5 31
4 34 0 0
5 38 0 0
6 15 5 33
7 21 5 24
8 14 5 36
9 32 0 0
10 11 5 45
11 22 12 55
12 11 4 36
13 19 0 0
14 12 2 17
There is a clinal decrease in the frequency of this polymorphic
character in all directions from the center of its distribution at
Daytona Beach (Sample 11). This decrease does not appear to be cor-
related with any environmental gradient.
The four characters disousmed above show little or no con-
cordance and do not provide a suitable basis for separating any of the
Table 6 summarizes the available information on the seasonal
distribution of the different stages of development. Most of these
data were taken from Emerton (1912) and Wallace (1942).
Table 6.-Observed seasonal population
composition of G. pikei
Stage of development F H A M J J A S 0 N D
Adult males X X
Adult females X X X X X X X X X X
Penultimate males X X X
Penultimate females X X X
Immatures X X X X X X X X X X X
Females with egg sacs X X
Females with young X X
*No data are available for January.
Penultimate males and females appear in June. These mature
and mate in August and September. The adult males have completed their
life span by October, but the females overwinter and lay their eggs in
May and early June. Females with young are found in late June and July.
These young represent the immatures found during August and September.
Thus the males and females which mature and mate during this period
were hatched the preceding year. This two-year cycle appears to be
typical of many species of Geolycosa. Although it takes two years for
the life cycle to be completed, males and females mature and mate every
Table 7 summarizes the available information on the seasonal
distribution of the different stages of development.
Table 7.-Observed seasonal population
composition of G. xera
Stage of development J F M A M J J A S 0 N D
Adult males X X
Adult females X X X X X X X X X X X
Penultimate males X X X X X
Penultimate females X X X X
Immatures X X X X X X X X X X X
Females with egg sacs X
Females with young X
Penultimate males and females appear every year in June.
These mature and mate in October and November. The adult males have
completed their life span by December, but the females overwinter and
lay their eggs in March. Females with young are found in April. These
young are still immature during the following October and November,
therefore, the males and females which mature during this period were
hatched the preceding year. This is a two-year cycle similar to that
of pikei, however, xera matures and mates later in the fall and its
eggs are laid earlier in the spring. The fact that xera lives in a
warmer climate probably accounts for these differences.
A consideration of the seasonal distribution of patellonigra
revealed a very different situation from that encountered in pikei and
xera which have a single breeding period during the fall of each year.
Although all of the populations of patellonigra follow the typical two-
year cycle, the seasonal occurrence of the breeding period varies
geographically, and in some areas there are two breeding seasons a
Table 8 summarizes the available information on the seasonal
distribution of the different stages of development in the populations
inhabiting Gilchrist, Clay, Putnam and western Volusia counties.
Table 8.-Observed seasonal population composition of G.
patellonigra in Gilchrist, Clay, Putnam and
western Volusia counties.
Stage of development J F M A M J J A S 0 N D
Adult males X X
Adult females X X X X X X X X X X
Penultimate males X X X X X
Penultimate females X X X X X
Immatures X X X X X X X X X X X
Females with egg sacs X
Females with young X
This life cycle is similar to that of pikei and identical to
that of xera.
The data for the populations inhabiting Marion and Hills-
borough counties are given in Table 9. In these counties the males
and females mature and mate in May instead of in the fall. Females
with young are found from August to October.
The populations in Levy, Alachua, Hernando and Sumter counties
have two breeding seasons a year (Table 10), one in March and April,
the other in October.
Table 9.-Observed seasonal population composition of
G. patellonigra in Marion and Hillsborough counties.
Stage of development F H A M J J A S 0
Adult male X
Adult female X X X X X X X XX
Penultimate male X X X
Penultimate female X X X
Immatures X X X X X X X X
Females with egg sac
Females with young X X X
No data are available for November through January.
The females with young in April probably represent those
females which mated the previous fall, while those in July represent
females which mated in the spring.
Information on the seasonal distribution of the different
stages of development in the populations on the East Coast is not as
complete as that for other areas. Data from eastern Volusia, Brevard
and Indian River counties are available only for February, March and
April. These are given in Table 11.
The fact that females with young are found in March, the
month following the breeding season, would indicate that these pop-
ulations breed twice in a year. In all the other populations of patel-
lonigra, and in xera and pikei, females are not found with young until
at least three months after the breeding period. Therefore, the females
with young found in March probably mated the preceding fall.
Farther down the coast in Martin, Palm Beach and Broward
counties, adult males and females, penultimate males and females and
immatures have been found in February. No data are available for the
other rionths so it is impossible at this time to say whether the pop-
ulations in the3e counties have a single or double breeding season.
Table 10.-Obterved seasonal population composition of
G. patellonira in Levy, Alachua, Hernando
and Sumter counties.
Stage of development J F I A M J J A S 0 N D
Adult males X X X
Adult females X X X X X X X T X X X X
Penultimate males X X X X X X X X X X
Penultimate females X X X X X X X X X X
Immatures X X X X X X X X X X X X
Female with egg saci X
Females with young X X
Figure 10 shows the geographic distribution of the various
breeding seasong throughout the rangc of 2atelIcnigra, 'Kith the ex-
ception of the population in Marion County, there it a change from
strictly fall breeders to fall and spring breeders as you go south.
ft the West Coast this change is completed in Hillsborough County
where the population is strictly a tpring breeder. A similar situation
may be encountered on the East Coast when more data are available from
the southern portion,
Geographic variation in non-morphological character, sucb
as time of breeding, are important factors in the proceqs of ipeciation
yet are difficult to evaluate bectvse of the paucity of information on
their genetic basis (Mayr, 1942). Te timing of the breeding sea*on in
the Y*riou4 populations studied above appears to be tmder genetic control,,
The fact tKkt the population in Marion County it strictly a spring breeder,
Figure 10. Geographic variation in breeding season in
t FALL 8 SPRING
in spite of its relatively northern location, would seem to preclude
the possibility that the breeding periodicity is strictly an onto-
genetic response to some north-south environmental gradient such as
An attempt was made to correlate the geographic differences
in breeding season with the geographic variation of the morphological
characters, but no definite correlations could be established.
Table 11.-Observed seasonal population composition of
G. patellonigra in western Volusia, Brevard
and Indian River counties
Stage of development F M A
Adult males X
Adult females X X X
Penultimate males X
Penultimate females X
Immatures X X
Females with egg sacs X
Females with young X
o No data available for May through January.
In xera and all the populations of patellonigra which have
a single breeding season, a curious situation is encountered. Although
it takes two years for the life cycle to be completed, males and
females mature and mate every year. Since the females which mature
in an even year have completed their life span before the males of
the next, or odd, year have matured, it would appear that populations
which mature in even and odd years are reproductively isolated. This
annual isolation within the same geographic and habitat area could
provide a possible method for sympatric speciation. Such annual
isolation has been considered to be a rare phenomenon (Emerson,
1949). However, Gabbutt (1959) has recently described a comparable
situation in some English populations of the wood cricket, Nemobius
sylvestris (Bosc.). He found that the crickets in these populations
had a two-year life cycle, and there was no evidence indicating over-
lap of the populations which matured in even and odd years.
If the populations which mature in even and odd years are
reproductively isolated, as they appear to be, it might be possible
to detect some morphological differences. In order to check this, a
comparison was made between two samples taken from a population in
Clay County which breeds only in the fall. One sample was collected
on Nov. 15, 1959, while the other was collected the following year on
the same date. Each sample consisted of ten females and one male. No
differences were found in the ventral color pattern or the structure
of the genitalia, and no statistically significant differences could
be demonstrated in the length of the carapace and epigynum. Differ-
ences may have been present and gone undetected since the samples were
small. Also both populations are living in the same area and are pre-
sumably responding to similar selection pressures.
In pikei and the populations of patellonigra with two
breeding seasons, females are present all year round so there it at
least a chance for gene flow between the populations which mature in
the even and odd years. It id of course possible that the females of
these populations can only be fertilized for a short period after they
mature. If this is the case, then the situation would become exceed-
ingly complex. In addition to an annual isolation, there would be a
superimposed, seasonal isolation in the populations with two breeding
seasons making four reproductively isolated populations. Alexander
and Bigelow (1960) have proposed that such a seasonal type of isolation
has provided the basis for the sympatric speciation of two closely-
related species of field crickets, Acheta pennsylvanicus and A.
POST-PLIOCENE HISTORY OF THE
SOUTHEASTERN COASTAL PLAIN
A brief summary of the general aspects of the Post-Pliocene
history of the lower southeastern Coastal Plain is necessary before
considering the present distribution, habitat relations and evolutionary
history of the pikei complex. The following account is based on in-
formation obtained from the publications of Cooke (1945), MacNeil
(1950), Flint (1957) and Laessle (1958).
During the Pliocene Florida was a peninsula. With the advent
of the first glaciation of the Pleistocene, the Nebraskan, there was a
drop in sea level, and this peninsula was considerably enlarged. The
subsequent Aftonian Interglacial raised the sea level again, and large
parts of Florida and Georgia were inundated. The 150-ft. Okefenokee
shoreline was formed at this time. Several islands and island groups
remained above the level of the Okefenokee Sea. Figure 11 shows the
location of this 150-ft. shoreline and the islands of the Okefenokee Sea.
There were three prominent island groups, one in North Central
Florida grouped about Trail Ridge, one just north of Tampa Bay and one
grouped around the Lake Wales Ridge. On his map of the Pleistocene
shorelines of Florida and Georgia MacNeil (1950) showed a small isolated
island just south of the Lake Wales Ridge as being the southernmost
island of the Okefenokee Sea. However, Laessle (1958) provided infor-
mation which confirmed the existence of another island, Red Hill, about
30 or 35 miles further south. Strong currents of the Okefenokee Sea
Figure 11. The approximate land areas of the Okefenokee
Sea superimposed on the present shore line of Florida and Georgia.
This map is a modification of that of MacNeil (1950). The arrows
show the direction of the stronger currents.
passed south and east of the Trail Ridge and Tampa Bay island groups
and separated them from the Lake Wales Ridge group. Other strong
currents passed between the latter group and Red Hill Island.
The next glacial period, the Kansan, was accompanied by
another drop in sea level. The rise in sea level during the following
Yarmouth Interglacial was not as great as that in the Aftonian, and a
new shoreline, the Wicomico, formed at the 100-ft. level. Figure 12
shows the location and extent of the early Wicomico islands. The
area occupied by the Trail Ridge Island group in the Okefenokee sea
was now connected to the mainland, but there was still a large island
in the central part of Florida. Red Hill island was connected to this
central island. The strong currents of the Wiconico sea passed between
the mainland and the large central island.
During the Sangamon Interglacial which followed the next
glaciation, the Illinoian, the 25 to 30-ft. Pamlico shoreline was
formed. Figure 13 shows the shoreline. Most of Florida was a pen-
insula, but there was a chain of islands down the East and West Coasts.
The final shoreline before the Recent was the 8 to 10-ft.
Silver Bluff. This is of Post-Wisconsin origin.
The various Post-Pliocene Interglacial stages and their
associated shorelines are summarized in Table 12. Also the estimated
duration of each of the Interglacials is given. These estimates were
taken from Kay (1931).
Figure 12. The approximate land areas of the early
Wicomico Sea superimposed on the present shorelines of Florida
and Georgia. This map is a modification of that of MacNeil.
The arrows show the direction of the stronger currents.
I SL AND
Figure 13. The approximate shore line of the Pamlico Sea
superimposed on the present shoreline of Florida and Georgia. This
map is a modification of that of MacNeil.
//////// ////////ii i
Table 12.-Estimated duration and associated shorelines
of the Post-Pliocene Interglacial stages.
Associated Altitude Duration
Stage shoreline in feet in years
Aftonian Okefenokee 150 200,000
Yarmouth Wicomico 100 300,000
Sangamon Pamlico 25-30 120,000
Post Wisconsin Silver Bluff 8-10 25,000
PRESENT DISTRIBUTION AND HABITAT RELATIONS
Figure 14 shows the distribution of the pikei complex in
Florida and Georgia. The range of pikei extends north to Massachusetts
and is restricted to a narrow zone along the Atlantic coast. The
distribution pattern that is shown for patellonigra and xera represents
their actual distribution fairly accurately. Numerous collecting trips
were made throughout Florida and southern Georgia. These trips were
arranged so that the territory was traversed in an east-west as well as
north-south direction. Therefore, the highly-restricted, north-south
distribution pattern is a reflection of their actual distribution
rather than an artifact brought about by the collecting method.
Emerton (1912) has described the habitats of pikei in New
England. They are never found far from the seashore and are especially
abundant in the sandy hills of Cape Cod. They are also found in the
dunes just in back of the beaches. In Georgia and South Carolina, this
species is found in sandhills which are as far as 60 miles inland. How-
ever, these sandhills are located in an area which was traversed by
shorelines during the Pleistocene.
Although patellonigra and xera are confined to areas in
Florida which have deep, well-drained, sandy soils, not all such areas
have been colonized. There are three different kinds of habitats which
hAve this type of sandy soil. They are the sandhills, sand-pine scrubs
and the active dunes of the coastal beaches. Neither patellonigra nor
Figure 14. itiuino th mebr of heE i
xera have been found inhabiting the active dunes. These dunes have been
colonized by G. micanopy Wallace, a widespread species in Florida which
is found in many types of habitat. The sandhills and sand-pine scrubs
are the only habitats from which patellonigra and xera have been taken.
The sand-pine scrubs are found on the nutrient-poor soils of
the St. Lucie and Lakewood series. The surface of both of these soils
consists of white, beach-like sand. The vegetation is xeromorphic and
is dominated by the sand-pine, Pinus clausa. Beneath the pines there
is a dense growth of evergreen shrubs but little or no herbaceous ground
cover. Areas of bare white sand are sometimes encountered.
The sandhill vegetation is found on soils of the Lakeland
series. Longleaf pine (Pinus australia) and turkey oak (Quercus
laevia) are the dominant trees and form open park-like stands. In
Florida, however, there are few virgin stands since most of the pine has
been logged off. The wire grasses, Aristida stricta and Sporobolus
gracilis, form most of the herbaceous ground cover. For a more complete
description of these vegetation types see Harper (1914, 1915 and 1921),
Cooke (1939), Kurz (1942) and Laessle (1942, 1958).
Although the sandhill and scrub areas are the only habitats
in which patellonigra and xera are found, not all of these areas have
been colonized. The reasons for this appear to be partly ecological
and partly historical. A consideration of the distribution of these
species in the sand-pine scrubs will illustrate the effect of these
ecological and historical factors.
Laeisle (1958) has discussed the origin of the soils Aupport-
ing these sand-pine scrubs. He reported that they apparently arose in
the following ways 1) Dunes, beaches and bars associated with Post-
Pliocene marine shorelines. 2) Submerged hilltops in the Pleistocene
seas. 3) Sand deposits washed and sorted by deep marine currents of
the Pleistocene seas. 4) Wave-washed shores of fresh-water lakes.
Although extensive collecting was done in scrubs of all these
types, only two types were found to be colonized by patellonigra and
xera. The bulk of the specimens were collected from dune scrubs.
If they had a rolling dune-like topography, scrubs formed on the washed
and sorted, marine, sand deposits also yielded specimens. This re-
striction to scrubs with a dune-like topography appears to be due to
ecological rather than historical factors. In areas where dune-like
and flat scrubs lie immediately adjacent and no barriers to migration
are evident, there has been no movement into the flat scrubs.
The apparent operation of an historical factor can be seen
when the distribution of these species in the various dune scrubs is
examined. No specimens have been taken from dune scrubs known to have
been formed on the Post-Wisconsin, 8 to 10-ft. Silver Bluff shoreline.
Although of more recent origin, these scrubs appear to be ecologically
similar to those formed on other Post-Pliocene shorelines. This absence
of patellonigra and xera from the Silver Bluff scrubs is best seen in
connection with the scrubs on the West Coast of Florida. On the East
Coast it is difficult to separate the Pamlico and Silver Bluff deposits.
The West Coast Silver Bluff scrubs are separated from those formed on
the Pamlico shoreline by fairly wide areas of flatwoods which are
subject to flooding and provide an unsuitable habitat for these species.
The best explanation for the absence of these spiders is that they have
limited dispersal powers and have not been able to reach these scrubs
yet. All of the Silver Bluff scrubs that have been examined were found
to be inhabited by G. micanopy.
Very little information is available on the origin of the
sandhills so it is difficult to assess the effect of the historical
factor on the distribution of xera and patellonigra in this habitat.
Extensive areas of Florida, especially in the northern half, are covered
with sandhills, but the distribution of these species within these areas
is very restricted. Those sandhill areas which have been colonized all
show a rolling dune-like topography. On the tops of these dune-like
ridges there are large open areas devoid of wire grass. The soil has
been heavily leached, and in some areas the surface is covered with an
almost white sand. Rosemary (Ceratiola ericoides), a plant which grows
on the soils which support sand-pine scrub and other poor soils, is
common in these areas. Patellonigra and xera inhabit the tops of the
ridges but are replaced by micanopy in the surrounding flatter area
where the wire grass is thicker. The ridges run for many miles in
narrow north-south bands through the more typical sandhill vegetation.
Their location and ecological appearance suggest that they were formed
in connection with Pleistocene shorelines but definite proof is lacking.
CONCLUSIONS CONCERNING THE EVOLUTIONARY
HISTORY OF THE COMPLEX
The most striking aspects of the taxonomy and distribution
of the pikei complex are the allopatric nature of the species and the
extent of speciation and infraspecific variation in the southern part of
the range. This situation is not unique to this complex. It has been
found in several other groups of animals inhabiting the lower south-
eastern Coastal Plain. These include such diverse groups as the
beetles of the genus Mycotrupes (Hubbell, 1954), the grasshoppers of
the puer group of the genus Melanopus (Hubbell, 1932, 1956) and the
snakes of the genus Stilosoma (Highton, 1956).
All of these groups share two common characteristics,
limited dispersal powers and a restricted habitat preference. The
grasshoppers of the puer group of the genus Melanoplus are flightless
and are found only in the sandhills of North Florida and in certain
flatwood areas in South Florida. The beetles of the genus Mycotrupes
are flightless and fossorial. They usually are found only in the sand-
hill areas. The snakes of the genus Stilosona are fossorial and have
been recorded from sandhills, sand-pine scrub and xeric hammock but are
not common in the two latter associations.
The extensive subspeciation or allopatric speciation shown
by the pikei complex and the other groups mentioned above is usually
found only in insular areas or areas where there are formidable natural
barriers. At the present time neither of these situations is character-
istic of the lower southeastern Coastal Plain. However,there is ample
evidence for the repeated existence of insular conditions during the
Post-Pliocene period. Both of the workers cited above came to the
conclusion that the present distribution and taxonomic relationship#
of their groups could beat be understood when correlated with this Post-
The pikei complex is a particularly favorable group in which
to study this correlation. In the southern part of its range it is
restricted to habitats which were formed in connection with the Post-
Pliocene shorelines. Also all the available evidence indicates that
these spiders have limited dispersal powers. They are fossorial ond
spend their entire life in the same burrow, enlarging it as they grow
older. The only opportunity for dispersal would be when the young letave
the mother's burrow. It is possible that they could disperse by balloon-
ing at this time, but these spiders have two characteristics which would
tend to negate this view. They form afta1 and very localized colonies
even though there are large areas of apparently suitable habitat be-
tween the colonies, and the burrow* of the young inmatures tend to be
clustered about the burrows of the old females. The absence of xerg
and patellonigrA from the seemingly ecologically suitable Silver Bluff
scrubs furnishes additional evidence of their limited dispersal powers,
Some of tha scrub# are located only about 30 vile* from inhabited
Pamlico scrubs. Although the spiders have h~d several thousand years
to ditperle to these scrubs, and although the prevailing windk khe
The following account of the evolutionary history of the
pikei complex is of course hypothetical, and alternative proposals are
possible. It does, however, provide an explanation for the present
distribution and taxonomic status of the complex which is consistent
with the available geological data.
I can be postulated that during the Pliocene and the
Nebraskan Glacial stage when Florida was a peninsula, a homogeneous
ancestral stock inhabited the entire Atlantic seaboard. The rise in
sea level during the following Aftonian Interglacial stage inundated
large parts of Florida and Georgia and caused three relatively large
populations to become isolated from this ancestral stock and from each
other. Each of these three populations was confined to an island or
island group in the Okefenokee Sea (Figure 11). One population in-
habited the Trail Ridge island group and possibly the Tampa Bay island
group also, another inhabited the Lake Wales island group, and the
third was confined to Red Hill Island. The strong currents of the
Okefenokee Sea served as formidable barriers separating these populations.
In view of the limited dispersal powers and narrow habitat
restriction of these spiders, there was probably little movement of
these populations from their Aftonian centers of distribution when the
water receded during the following Kansan Glacial stage.
Since the rise in sea level during the next Interglacial, the
Yarmouth, was not as extensive, the Trail Ridge island group remained
incorporated into the mainland and Red Hill Island was attached to the
large Central Florida island of the Wicomico Sea (Figure 12). This
large island was separated from the mainland by strong marine currents.
Although the Trail Ridge group formed part of the mainland, little gene
flow was possible between the ancestral mainland population and the
Trail Ridge population because of the presence of extensive swampland
in the area which separated the Trail Ridge island group from the main-
land during the Okefenokee period. However, because of the land
connection and absence of swampland there was opportunity for gene flow
between the populations on the Lake Wales Ridge and Red Hill Island.
At the end of the Yarmouth Interglacial, there were three
major populations which had been isolated from one another since the
Aftonian Interglacial. One inhabited the mainland north of the
Okefenokee Swamp, and another the area about the Trail Ridge, while
the third was located in the Lake Wales Ridge area. During this period
of isolation these populations achieved the specific status now re-
presented by pikei, patellonigra and xera, respectively.
During the Aftonian Interglacial the population which
differentiated into xera was separated into a northern and southern
segment. The northern portion inhabited the Lake Wales Ridge island
group, the southern the Red Hill Island. Although these areas have
been reunited since that period, these two segments presumably attained
subspecific status during this period of isolation and are now represent-
ed by the subspecies xera and archboldi.
All through the Sangamon Interglacial stage and up to the
present time, the areas inhabited by patellonigra and xera have re-
mained in contact. During this period, these species extended their
ranges northward and southward from their centers of origin. The
northern movement of patellonigra was halted by the unfavorable habitant
in southern Georgia while the southern movement of xera was halted by
the swampy Everglades region. In Central Florida these two species
came into contact, but they have similar habitat requirements, and the
competition at their lines of contact has maintained their original
allopatry. However, patellonigra was able to move southward around
the range of xera by utilizing the chain of Pamlico islands which lay
along each coast (Figure 13).
An idea of the approximate amount of time available for the
events discussed above can be obtained from Table 12. The chronology
given in this table is based on the assumption that the last glacial
drift sheet is 25,000 years old. Recent radioactive dating methods
place this figure considerably lower (Flint, 1957), therefore,this
chronology should only be used to get a general idea of the order of
magnitude of the time involved.
As is suggested above,a strong case can be made to substanti-
ate the thesis that the southern species and subspecies of the pikei
complex differentiated on Pleistocene islands. If this theory is
accepted, one important question remains unanswered. By what genetic
mechanism was this differentiation brought about?
One possible mechanism would be genetic drift. If this had
been operative, it would have to be assumed that the populations on
the Pleistocene islands were quite small. This assumption seem un-
warranted if the number of individuals now inhabiting areas similar in
size and ecology to these Pleistocene islands can be used in judging
A more reasonable explanation would be one of those offered
by Mayr (1954) to explain the conspicuous differences shown by many
peripherally isolated populations. He pointed out that in a species
with a widespread range, such as that of the ancestral stock of the
pikei complex, there is a constant flow of genes and gene complexes
from the central part of the range into the marginal populations at
the periphery. These genes and gene complexes which are adaptive in
the central part of the range may not be so in these marginal popula-
tions. Thus the outlying populations must constantly be making genetic
adjustments which will adjust the influx to the requirements of their
If these marginal populations become isolated from the main
populations, as those in the southern part of the range of the ancestral
stock of the pikei complex were during much of the Pleistocene, those
genes and gene complexes which had flowed in from the main populations
would disappear if they were not adaptive in the environment of the
isolated populations. New gene combinations would be formed which
would be better adapted for the environments of these populations.
Since the selective forces and the results of the mutational process
would be different in each population, this would lead to genetic
divergence which could eventually result in the establishment of re-
productive isolation and of speciation.
Alexander, R. D. and R. S. Bigelow 1960. Allochronic speciation in
field crickets, and a new species, Acheta veletis. Evolution,
14 (3): 334-346.
Brown, W. L. and E. 0. Wilson 1956. Character displacement. Syst.
Zool., 5 (2): 49-64.
Barnes, R. D. 1959. The lapidicina group of the wolf spider genus
Pardosa. Amer. Mus. Novitates, 1960: 1-20.
Carr, A. F., Jr. 1940. A contribution to the herpetology of Florida.
Gainesville: University of Fla. Press, Biol. Sci. Series III
Cooke, C. W. 1939. Scenery of Florida as interpreted by a geologist.
Fla. Geol. Surv. Bull., 17: 1-118.
S1945. Geology of Florida. Ibid., 29: 1-339.
Emerson, A. E. 1949. Ecology and isolation. (pp. 605-630 in Principles
of Animal Ecology by Allee et al., Philadelphia and Lonaon: W. B.
Saunders Co. 837 pp.).
Emerton, J. H. 1912. Four burrowing Lycosa (Geolycosa Montg.,
Scaptocosa Banks) including one new species. Psyche, 19i 25-36.
Flint, R. F. 1957. Glacial and Pleistocene Geology. New York: John
Wiley and Sons. 553 pp.
Gabbutt, P. D. 1959. The bionomics of the wood cricket, Nemobius
sylvestris (Orthoptera: Gryllidae). Jour. Animal Ecol.,
28 (I): 15-42.
Harper, R. M. 1914. Geography and vegetation of northern Florida.
Fla. Geol. Surv., Gth Ann. Rept., 163-451.
S1915. Vegetation types; natural resources in an area in central
Florida. Ibid., 7th Ann. Rept., 135-188.
1921. Geography of central Florida. Ibid., 13th Ann. Rept.,
Highton, R. 1956. Systematics and variation of the endemic Florida
snake genus Stilosoma. Fla. State Mus. Bull., 1 (2): 73-96.
Hubbell, T. H. 1932. A revision of the uer group of the North
American genus Melanoplus with remarks on the taxonomic value
of the concealed male genitalia in the Cyrtacanthacrinae
(Orthoptera, Acrididae). Misc. Publ. Univ. Mich. Mus. Zool.,
1954. Relationships and distribution of Mycotrupes. (pp. 39-51
in The burrowing beetles of the genus Mycotrupes by A. L. Olson
eT al. Misc. Publ. Univ. Mich. Mus. Zool., 84: 1-59).
1956. Some aspects of geographic variation in insects. Ann.
Rev. Entomology, It 71-88.
Kay, G. F. 1931. Classification and duration of the Pleistocene
period. Geol. Soc. America Bull., 42: 425-466.
Kurz, H. 1942. Florida dunes and scrubs, vegetation and geology.
Fla. Geol. Surv., Geol. Bull., 23, 1-154.
Laessle, A. M. 1942. The plant communities of the Welaka area.
Gainesville: University of Fla. Press, Biol. Sci. Series,
IV (1)1 1-143.
1958. The origin and successional relationship of sandhill
vegetation and sand-pine scrub. Ecol. Monog., 281 361-387.
MacNeil, F. S. 1950. Pleistocene shorelines in Florida and Georgia.
U. S. Geol. Surv. Prof. Paper, 221-FI 95-107.
Maerz, A. J. and M. R. Paul 1930. Dictionary of Color. New Yorks
McGraw-Hill. 207 pp.
Mayr, E. 1942. Systematics and the Origin of Species. New York:
Columbia Univ. Press. 334 pp.
1954. Change of genetic environment and evolution. (pp. 157-
180 in Evolution as a Process ed. by J. S. Huxley et al., Londons
Geo. Allen and Unwin Ltd. 367 pp.).
SE. G. Linsley and R. L. Singer 1953. Methods and Principles
of Systematic Zoology. New Yorks McGraw-Hill. 328 pp.
Montgomery, T. H. 1904. Descriptions of North American Araneae of
the families Lycosidae and Pisauridae. Proc. Acad. Nat. Sci.
Phil., 561 261-323.
Neill, W. T. 1957. Historical biogeography of present day Florida.
Fla. State Mus. Bull., 2: 175-220.
Simpson, G. G., A. Roe and R. C. Lewontin 1960. Quantitative Zoology.
New Yorki Harcourt, Brace and Co. 440 pp.
Wallace, H. K. 1942. A revision of the burrowing spiders of the genus
Geolycosa (Araneae, Lycosidae). Am. Midl. Nat., 27: 1-62.
.1942. A study of the lenta group of the genus Lycosa, with
descriptions of new species (Araneae, Lycosidae). Amer. Mus.
Novitates, 1185: 1-21.
John David McCrone was born November 9, 1934, at Somerville,
Massachusetts. In June, 1952 he was graduated from Concord High
School. From 1952 to 1954 he attended Northeastern University,
Boston, Massachusetts. In 1954 he transferred to the University of
Florida, where he received his Bachelor of Science degree in 1956.
He entered the Graduate School in the University of Florida the same
year. Here he held a research assistantship and pursued studies in
biology and biochemistry. In 1957-1958 he served in the United States
Army. He re-entered the University of Florida in 1958 and held
graduate and teaching assistantships and pursued studies in biology
and entomology. In 1960-1961 he held a fellowship from the Southern
John David McCrone is married to the former Hazel Marie
Dixon. He is a member of the Association of Southeastern Biologists,
Phi Sigma Honorary Biological Society and the Newell Entomological
This dissertation was prepared under the direction
of the chairman of the candidate's supervisory committee and has
been approved by all members of that committee. It was submitted
to the Dean of the College of Arts and Sciences and to the Gridaite
Council, and was approved as partial fulfillment of the require-
ments for the degree of Doctor of Philosophy.
August 12, 1961
De~a, College of.i::"
Arts and Scienc:ls;Iu
Dean, Graduate School
T/f^j .......... i