Group Title: study of the Geolycosa pikei complex in the southeastern United States
Title: A Study of the Geolycosa pikei complex in the southeastern United States
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Title: A Study of the Geolycosa pikei complex in the southeastern United States
Physical Description: iv, 80, 1 leaves. : illus. ; 28 cm.
Language: English
Creator: McCrone, John D
Publication Date: 1961
Copyright Date: 1961
 Subjects
Subject: Geolycosa pikei   ( lcsh )
Spiders -- Southern States   ( lcsh )
Zoogeography   ( lcsh )
Biology thesis Ph. D   ( lcsh )
Dissertations, Academic -- Biology -- UF   ( lcsh )
Genre: bibliography   ( marcgt )
non-fiction   ( marcgt )
 Notes
Thesis: Thesis - University of Florida.
Bibliography: Bibliography: leaves 77-79.
Additional Physical Form: Also available on World Wide Web
General Note: Manuscript copy.
General Note: Vita.
 Record Information
Bibliographic ID: UF00097987
Volume ID: VID00001
Source Institution: University of Florida
Holding Location: University of Florida
Rights Management: All rights reserved by the source institution and holding location.
Resource Identifier: alephbibnum - 001033947
oclc - 18218689
notis - AFB6226

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A STUDY OF THE GEOLYCOSA PIKEI

COMPLEX IN THE SOUTHEASTERN

UNITED STATES









By
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
August, 1961











ACKNOWLEDGEMENTS


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


Page

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


Table Page

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


Figure Page

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
iv











INTRODUCTION


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 area.











METHODS


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

the animal.

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

millimeter.

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

lamp.

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,

respectively.

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.








SPECIES CRITERIA




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.











TAXONOMY


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,

several imm.

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.

8








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






























































4-1


0


C) r-q







,3



-4




13



















.. m








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);
DeBary (4).

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.
27 (45).

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.































2








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










S AAPLF.


(27) L
(27) L


El----


A45) L


-I
-J^


(17)



.-aE


-F--
(25)


4


9


MILLIMETERS


-15) L






























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.










(27)


(15)


(45)


(9)


(17)


at


3--


6 (19-


7 (25)


13-


MICROMETER UNITS


SAMPLE


---t----


p








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.





24























SAMPLE W








33


27




44

4 4m








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

complex.

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

as carapace,

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.





30


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
(2).

Sample 14. Broward Co.: Ft. Lauderdale (6); Delray Beach
(6).

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.




35










6

5 7
8

4 9
I I
I0



O
S12





13










14





























Figure 7.
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










SAMPLE




2

3

4

5

6

7

8

9

10

II

12

1 3

14


(19)




(34)




|15)












(22)


(11)



1 2-


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
Table 4.









SAMPLE











6

2(21

8 (14_.ELZ i

4
(32)













I I I I

15 16 17 18 19 20 21 22 23 24 25 26


MICROMETER UNITS







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.


















In~~li


SAMPLE
I


2


8
- 3


I I 3


'A


7 8

'8


4


3 4 3


?


12

1 1__-3


I 7








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





45


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

populations taxonomically.










SEASONAL DISTRIBUTION

G. pikei


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

Month*
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

year. A







G. xera


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

Month
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.


G. patellonigra


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

year.

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.


Month
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.

Month*
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





50


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.


Month
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,

h I































Figure 10. Geographic variation in breeding season in
G. patellonigra.








0
c


0


FALL \
t FALL 8 SPRING
O SPRING


0
S


0








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

temperature.

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


Month*
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.


Discussion


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.

veletis.











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.























_TRAIL
RIDGE


LAKE WALES


ISLAND


18
e0 11







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.



















































RED HILL
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

Illllllllllliii

1111111111 11111111
iiiiiiiiii





64


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




















O
0
O

OO
O


O A

0o A
A
0 A
A

PIKEI \
PATELLONIGRA
XERA XERA


D


ARCHBOLDI







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-





72


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-

Pliocene insulAtion.

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

former density.








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

own environments.

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.











LITERATURE CITED


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
(1): 1-118.

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.,
71-307.








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.,
231 1-64.

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.




79


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.










BIOGRAPHICAL SKETCH


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

Regional Fund.

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

Society.











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


Supervisory Cotmittee:



,Chai rfan


T/f^j .......... i


/^^^




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