systematics of the eastern ratsnake complex (elaphe obsoleta)

Herpetological Monographs, 15, 2001, 1-53 ? 2001 by The Herpetologists' League, Inc.

SYSTEMATICS OF THE EASTERN RATSNAKE COMPLEX (ELAPHE OBSOLETA)

FRANK T. BURBRINK

Department of Biological Sciences and the Museum of Natural Science, 119 Foster Hall, Louisiana State University, Baton Rouge, LA 70803, USA

ABSTRACT: The eastern ratsnake, Elaphe obsoleta currently includes seven highly variable and taxonomically confusing subspecies. Recently, maximum likelihood and maximum parsimony phylogenetic analyses of two mitochondrial gene sequences suggested that the complex of E. obsoleta (including E. bairdi) is composed of four distinct evolutionary lineages found in four geographical areas: 1) an eastern clade located east of the Apalachicola River and the Appalachian Mountains, 2) a central clade located west of the Apalachicola River and the Appalachian Mountains and east of the Mississippi River, 3) a western clade located west of the Mississippi River, and 4) E. bairdi is located in southwest Texas and northeastern Mexico. With respect to this phylogeographic hy- pothesis, the former seven subspecies of E. obsoleta do not represent distinct evolutionary lineages.

In this paper, the morphology of Elaphe obsoleta and E. bairdi is compared to the results of the previous molecular study. Univariate and multivariate analyses of 67 morphological characters scored from 1006 specimens provided statistical support for the recognition of the same four evolutionary lineages identified in the phylogeographic study. Specimens can be classified morphologically by using canonical discriminant function analysis into the four molecular clades more accurately than they can be grouped into subspecific categories. Moreover, the identification of these subspecies proved difficult when using the traditional characters ascribed to them. In light of the corroborating molecular and morphological evidence, it is suggested that the recognition of the subspecies of E. obsoleta be discontinued. Instead, the four molecular clades should be recognized as four species: 1) eastern clade = E. alleghaniensis, 2) central clade = E. spiloides, 3) western clade = E. obsoleta, and 4) E. bairdi = E. bairdi.

Key words: Eastern Ratsnake; Phylogenetic Analysis; Subspecies; Morphology; Univariate and Multivariate Statistics; Elaphe alleghaniensis; E. spiloides; E. obsoleta; E. bairdi

THE COMMON EASTERN RATSNAKE is

represented by seven geographic subspecies with distinct color patterns distributed throughout the forested regions of the central and eastern United States (Fig. 1). Using complete sequences of two mitochondrial genes, Burbrink et al. (2000) showed Elaphe obsoleta consists of three geographically distinct clades: 1) an eastern clade, located east of the Apalachicola River and Appalachian Mountains, 2) a central clade, located west of the Appala- chian Mountains and the Apalachicola Riv- er and east of the Mississippi River and 3) a western clade, located west of the Mis- sissippi River (Fig. 2). Elaphe bairdi, rep- resents a fourth clade closely related to the western clade. These four lineages suggest that the current taxonomy, which recognizes seven highly variable subspecies, may be in error with respect to the evolutionary history of this group. In this paper, the eastern ratsnake complex is examined to determine if the morphology of

this group supports a taxonomic system that recognizes the four molecular clades or one that supports the recognition of the seven subspecies. Alternatively, it is possible that the morphology may not be con- cordant with either molecular or subspecific systems, but rather reflects a yet unknown situation.

Only a few studies have examined the morphology of Elaphe obsoleta. Unfortu- nately, only superficial color pattern characters were used to support various subspecific taxonomic names. Adults of all of the current subspecies are defined by the presence or absence of blotches or stripes, or whether the ground color is black, gray, brown, yellow or orange. Over the past 176 years, the following seven subspecies of E. obsoleta have been described based on those color patterns: E. o. obsoleta, E. o. quadrivittata, E. o. lindheimeri, E. o. spiloides, E. o. deckerti, E. o. williamsi, and E. o. rossalleni. Elaphe bairdi was considered a subspecies of E. obsoleta, but

1

2 HERPETOLOGICAL MONOGRAPHS [No. 15

ff-

E.o. ob sleI

- - - . -k7;

r-,

, E. o. obsoleta

FIG. 1.-Geographic distribution of Elaphe obsoleta subspecies and E. bairdi.

was elevated to species status by Olson (1977). Another distinct form, E. o. parallela, was described by Barbour and En- gels (1942), but has since been considered an intergrade between E. o. quadrivittata and E. o. obsoleta (Neill, 1949).

Currently, the following key characters are used to define these subspecies:

Elaphe obsoleta obsoleta (Say, 1823): dark brown or black dorsum with little evidence of any pattern (Wright and Wright, 1957; Conant and Collins, 1991). Many adult individuals within the range of this subspecies display distinct dorsal blotches as seen in E. o. lindhiemeri and E. o. spiloides (Schultz, 1996).

Elaphe obsoleta quadrivittata (Hol- brook, 1836): four dark dorsal stripes on a ground color of yellow, tan, olive or gray (Conant and Collins, 1991; Schultz, 1996). Many specimens display blotches between the two most dorsal stripes (Schultz, 1996).

Elaphe obsoleta lindheimeri (Baird and Girard, 1853): 25-35 large dorsal blotches on a brown, yellow, or orange ground col- or. Considerable variation in ground color may make this subspecies difficult to distinguish from E. o. spiloides and E. o. ob-

soleta in areas where their distributions approach one another (Conant and Col- lins, 1991; Schultz, 1996).

Elaphe obsoleta spiloides (Dumeril, Bi- bron, and Dumeril, 1854): resembles E. o. lindheimeri, in retaining the juvenile blotched color pattern. Dorsal ground col- or in E. o. spiloides tends to be gray or grayish-white, whereas that of E. o. lindheimeri is brown, yellow, orange, or red.

Elaphe obsoleta deckerti (Brady, 1932): four brown longitudinal stripes on an orange, yellow, or tan ground color. Distin- guished from E. o. quadrivittata in retaining the juvenile blotches (Neill, 1949; Wright and Wright, 1957).

Elaphe obsoleta williamsi (Barbour and Carr, 1940): intermediate between E. o. spiloides and E. o. quadrivittata. Dorsum exhibits both blotches and stripes on a ground color of white or gray (Wright and Wright, 1957; Schultz, 1996).

Elaphe obsoleta rossalleni (Neill, 1949) similar to E. o. quadrivattata and E. o. deckerti. Ground color may be orange, orange yellow, or orange brown with four poorly defined longitudinal stripes. Pres- ence of a red tongue in E. o. rossalleni distinguishes it from the black tongued E.


2001] HERPETOLOGICAL MONOGRAPHS 3

63 ["Loudoun Co.,VA(6,0) sper Co. S,SC I(11Q)

81 -i, I Orange Co.,NY (4, 0) ".lLRockingham Co.,VA (7, 0) I Frederick Co.,MD (5, O)

rAlachua Co.,FL (14, Q) 4t- Hernando Co., FL (21, Q)

Putnam Co.,FL (13, Q) Monroe Co.,FL 1 (17, D)

82 iMonroe Co.,FL 2 (18, D) - Middlesex Co.,CT 1(2, O) -Middlesex Co.,CT 2 (3, 0) -Perquimans Co.,NC (8, 0) -Wake Co.,NC (9, O) - Chatham Co.,GA (12, Q)

98 -7VWliamsburg Co.,SC (10, Q) 98 W-ki-f-" r Di 11 nl

Eastern Clade

washingion co.,RI '1, u) jBroward Co.,FL (15, R

97 'Pinellas Co.,FL (20, Q) Dade Co.,FL (16, R)

99 -Sarasota Co.,FL (19, Q)

00r Liberty Co., FL (26, S) TaylorCo (24 S)

[Levy Co. FL1 (22, VS Levy Co. FL 2 (23, W)

Stark Co.,OH (71, 0) -Grundy Co.,TN(65,0) -Knox Co.,TN (69,0)

65 -Talladega Co.,AL(67, L) -St. Claire Co.,IL (61, L)

-Wood Co.,WV (72, 0) 0oo 96 -Madison Co.,AL (66, 0)

,Pike Co.,IL (60,0 ) Delaware Co,,OH (70, 0)

52 r Wakulla Co.,FL(25, S) Central T Walton Co.,FL (27, S) i Santa Rosa Co.,FL (28, S) C l

80? Tangipahoa Par.,LA 2 (25, L) Clade eL' St. Tammany Par.,LA 1 (33, L)

St. Tammany Par.,LA 2 (34, L) ., 5Johnson Co.,IL (63, L)

Z I 'Gallatin Co.,IL (62, L) Decatur Co. TN(64, L) Craighead Co.,AR (59, L)*

99 -Baldwin Co. AL (29, S) -East Feliciana Par.,LA (39, L) - East Baton Rouge Par., LA 1 (40, L) - Orleans Par.,LA (32, L) - Hinds Co.,MS (31, L)

Forrest Co.,MS (30, L) r Tangipahoa Par.,LA 1 (36, L)*

I-l_--I_ I_Iv -tEvangeline Par.,LA(44, L) 0 10 20 '-Natchitoches Par.,LA(46, L) Branch Length 83 -East Baton Rouge Par., LA 2 (41, L)* W este] - St. Landry Par.,LA(43, L) - Terrebone Par.,LA 1 (37, L) - Iberville Par.,LA (42, L) Clade - Cameron Par.,LA (45, L) C ade

Terrebone Par.,LA 2 (38, L) IGeary Co.,KS (55, 0)

100 74 Greene Co.,MO(56, O) 7 I Sumner Co.,KS (54, L)

'.. Cleveland Co.,OK (53, L) Garland Co.,AR (58, 0)

'79 Madison Co.,AR (57, 0) 9 100 Medina Co.,TX(48, L)

76 - Comal Co.,TX(47, L) " ' -Kerr Co.,TX(49, L)

Palo Pinto Co.,TX(52, L) 100 I Jefferson Davis Co.,TX 1(0, B I,

Jefferson Davis Co.,TX 2(51, B) I Elaphe bairdi

r

FIG. 2.-Bootstrap strict consensus tree for 18,479 maximum parsimony trees of length 424 steps. Numbers in parentheses correspond to localities listed in Burbrink et al., 2000. Letters in parentheses correspond to subspecies of Elaphe obsoleta, where: 0 = obsoleta, Q = quadrivittata, D = deckerti, S = spiloides, R = rossalleni, W = williamsi, L = lindheimeri, and B = Elaphe bairdi. Specimens found outside of the geographic area represented by their clade are marked with 0 (Burbrink et al., 2000).

o. quadrivittata and E. o. deckerti (Wright and Wright, 1957).

Elaphe bairdi (Yarrow, 1880 [in Cope, 1888]) considered a subpecies of E. obsoleta but elevated to species status by Olson (1977). The tail in E. bairdi is slightly longer than the tail in any subspecies of E. obsoleta. It often has four poorly defined longitudinal stripes and numerous dorsal blotches. The dorsal coloration is generally brown or gray with a wash of yellow or orange at the edge of each scale (Conant and Collins, 1991). Superficially, E. bairdi resembles E. o. quadrivittata.

All subspecies of Elaphe obsoleta display

dorsal blotches as juveniles. As E. o. obsoleta, E. o quadrivittata, E. o. rossalleni, E. o. deckerti, and E. bairdi develop, the blotched pattern tends to become obscured. Adults of E. o. spiloides and E. o. lindheimeri display the juvenile blotch pattern. Adults of Elaphe obsoleta williamsi retain the juvenile blotches while express- ing the adult stripes (Wright and Wright, 1957; Schultz, 1996).

It has been assumed that intergrades occur where the ranges of subspecies abut (Neill, 1949; Schultz, 1996). However, there are no intergrades between E. o. lindheimeri and E. o. bairdi (Lawson and

Elapne vulpina



Lieb, 1990). Please note that in Fig. 1, the range of E. o. spiloides and E. o. lindheimeri has been altered from the maps in Conant and Collins (1991). Blotched specimens with a gray ground color (E. o. spiloides) are found only in eastern Alabama and northern Florida.

Only two short studies have attempted to examine the range of color pattern variation in Elaphe obsoleta. Neill (1949), with no mention of actual specimens examined, stated that E. o. obsoleta, E. o. spiloides (referred to in his paper as E. o. confinis), E. o. williamsi, E. o quadrivittata, E. o. rossalleni, E. o deckerti, and E. o. lindheimeri were all valid subspecies. No mention was made of E. bairdi. Based on color pattern observations on less than 150 specimens, Dowling (1951, 1952) considered only four subspecies: E. o. obsoleta, E. o. spiloides, E. o. quadrivittata, and E. o. bairdi. Elaphe o. rossalleni, E. o. deckerti, and E. o. williamsi were placed in synonomy with E. o. quadrivittata. Ela- phe bairdi was considered a subspecies of E. obsoleta because Dowling (1951) assumed that this taxon intergraded with E. o. lindheimeri.

Subsequently, Wright and Wright (1957) considered all seven subspecies valid and placed them in their Handbook of Snakes. Conant (1975) also recognized all seven subspecies, but omitted E. o. deckerti and E. o. williamsi in later editions of his field guide (Conant and Collins, 1991).

Other studies have examined geographic variation of color patterns only in lim- ited portions of the range of Elaphe obsoleta. In their study of the herpetofauna of southern Florida, Duellman and Schwartz (1958) considered E. o. rossalleni as a subspecies distinct from E. o. quadrivittata based on color pattern. They re- garded the differences between the Flor- ida Key populations of E. o deckerti and the mainland E. o. quadrivittata to be triv- ial and thus did not recognize E. o. deckerti. Christman (1980), when examining patterns of geographic variation in Florida snakes, found no characters to support E. o. rossalleni, but did find the color pattern of E. o. deckerti to be distinct from E. o. quadrivittata. He also maintained that E.

o. spiloides was a valid subspecies and that E. o. williamsi should be considered an intergrade between E. o. spiloides and E. o. quadrivittata. The recognition of E. o. deckerti as an endemic form in the Florida Keys was also supported by Paulson (1968). Olson (1977), considering color patterns and scale counts, determined that intermediate forms between E. o. bairdi and E. o. lindheimeri were rare hybrids. Based on this evidence, he suggested that E. bairdi be recognized as a full species. Moreover, Parmley (1986) described differences in trunk vertebrae between E. obsoleta and E. bairdi. Lawson and Lieb (1990) used allozyme, scale count, and col- or pattern data to demonstrate that there is only a narrow zone of hybridization due to secondary contact between E. bairdi and E. o. lindheimeri, thus supporting Ol- son's claim that E. bairdi should be recognized as a distinct species.

This paper examines a much broader range of morphological variation in Elaphe obsoleta and E. bairdi based on 67 measurements of head and body scales and color pattern characters. The morphological data will be examined in light of the molecular phylogenetic information that have been discovered for this group to determine if concordance with the molecular clades exists.

MATERIAL AND METHODS

A total of 1006 specimens of Elaphe obsoleta and E. bairdi were examined during this study (Appendix I). Samples were obtained throughout the ranges of both species (Fig. 3). Specimens were classified into the four following groups as best determined by the ranges of the four molecular clades: 1) eastern clade if they were collected east of the Apalachicola River and the Appalachian Mountains, 2) central clade if they were collected west of the Apalachicola River and east of the Missis- sippi River, 3) western clade if they were collected west of the Mississippi River, and 4) E. bairdi if they were collected from southwest Texas and display characters representative of that species. The subspecific identity of each specimen was also determined using the traditional characters


201 HEPTLGIA OOGAH

. S_ 3' 41

14

* 25

13

I3

FIG. 3.-Map of the United States showing the general location of specimens examined in this study. Specimens are grouped by the putative ranges of the molecular clades. Values next to dark areas indicate the number of specimens examined from that locality. Individual specimens are plotted with a single dot.

for each taxon described in the introduc- tion.

Descriptions of all meristic and mensural characters measured on each specimen, and their abbreviations, are listed in Ap- pendix II. Characters that are discussed in a long list are referred to by their number in Appendix II. Many of these characters

PW

are illustrated in Figs.4-7. Characters 3, 4, 7, 8, 9, and 10 were discarded prior to the statistical analyses, because of lack of variation between specimens, clades or subspecies. All statistical analyses were performed using the program Systat 8.0 (SPSS, 1998).

Elaphe obsoleta and E. bairdi exhibit

WA I1 ,-' PrFWP

HL

FWP

FIG. 4.-Illustration of characters measured on the head and dorsal head scales of Elaphe obsoleta and E. bairdi.



PROW

5LRW

LL

FIG. 5.-Illustration of characters measured on the lateral and ventral head scales of Elaphe obsoleta and E. bairdi.

continuous growth and a bias in size of mensural characters between juveniles and adults occurs. Therefore, an attempt was made to minimize allometric influences due to differences in patterns of growth between juveniles and adults (Thorpe and Leamy, 1983). Fig. 8 demonstrates that the change in the HL/SV ratio diminishes near SV lengths of 500 mm. That is, the steep cline due to changes in SV/HL begins to flatten at SV values of 500 mm. Therefore, only specimens with a SV length greater than 600 mm were included in the study, insuring the exclusion of specimens exhib- iting juvenile ontogenetic growth patterns. The change in ratios of other mensural characters also decreases at SV lengths of 500 mm.

Adult specimens can vary in size from 600 mm to almost 2000 mm in this study. Because size is assumed to be less herita- ble than shape, an attempt must be made to insure that the differences among mensural characters in clades refer only to shape (Gould, 1966; Corruccini, 1975; Reist, 1985). To produce a linear relation- ship between all variables and reduce the effect of individual size variation, mensural characters were transformed logarithmi- cally (Hills, 1978; Thorpe and Leamy, 1983; Sokal and Rohlf, 1995). As demonstrated by Reist (1985, 1986), a univariate

computation of residuals provides the best estimate of shape of characters in ecto- thermic vertebrates with continuous growth. Residuals of mensural characters were obtained by regressing each variable against a character that is a good indicator of size. Standard residuals of the logo0- transformed head (35) and body measurements (34, 66, and 67) were obtained by regressing each against the log-transformed SV (33). Residuals of the log-transformed head measurements (36-65) were produced by regressing each against the log-transformed HL (35). Sexual dimorphism for all characters was tested using a Student's t-test. Male and female data were analyzed separately to minimize the possible effects of sexual dimorphism.

All raw characters were first examined for statistical significance between the four molecular groups (eastern clade, central clade, western clade and E. bairdi) using ANOVA with a Bonferroni adjustment. Student's t-test was used to determine if characters were significantly different between sex within each clade.

Canonical discriminant function analysis (DFA) was performed on meristic variables and the residuals of the log,0-transformed mensural variables. This technique was used to determine if it is possible to differentiate among a priori groups by us-



LBW 1

LBW 2

"-- , , ~^ \.',- ' ' ' ' t IVR

- -I | DSRI

_Co- -.- Bfg'\ -_

.,,- a_. ;

_ -

_

, ,.

, . - - .

DBW 2

DBW I

FIG. 6.-Illustration of selected pattern and body bairdi.

ing the available measurements (Manly, 1994). This technique maximizes the separation between groups and accounts for within-group variance and correlation. DFA has been successful in differentiating closely related lineages of snakes using morphological data (referred to as CVA in Thorpe 1976, 1980, 1983, 1987; Wiister and Thorpe, 1992; Wiister et al., 1995). DFA may help determine which morphological characters best influence the inclu- sion of an individual into a specific molecular clade.

DFA was implemented on female and male data separately, as well as female and

scale measurements made on Elaphe obsoleta and E.

male data combined. Four non-mutually exclusive sets of characters were examined using DFA to determine which sets of characters best distinguish clades morpho- metrically. The first set, Case 1, includes all mensural characters (34-67). The second set, Case 2, includes non-color meristic characters and all mensural characters (1, 2, 5, 11, 13-16, and 34-67). The third set, Case 3, includes all meristic characters, mensural characters and some color (1, 2, 5, 11, 13-17, 19, 21, 23, 25, 31, 32, and 34-67). The fourth set, Case 4, includes only variables with F-ratio values higher than 5.0 (significant at P < 0.001).



LSW DSW

F -- I-

j

-

- N

FIG. 7.-Illustration of dorsal body stripe measurements made on Elaphe obsoleta and E. bairdi.

Classification matrices based on DFA scores for each Case were produced to determine how well individuals were classified into their correct molecular groups. Using all Case 2 variables, a classification matrix was produced from DFA scores that attempted to maximize differences between subspecies. Specimens that could not be identified correctly as one of the seven subspecies or appeared intermediate between subspecies were not used. This eliminated bias in identification of subspecies and allowed a fair comparison of the different classification matrices that attempt to place individuals in their correct molecular clades or their correct subspecies based on all morphological traits that exclude color pattern bias.

Principal components analysis (PCA) also was used on all Case 3 variables to

determine if groups can be separated mor- phometrically without an a priori hypoth- esis of group membership. Differences among groups on each axis were tested using ANOVA with a Bonferroni adjustment.

It should be noted that certain characters were not used in the multivariate analyses. No residual variable exists for SV (33) because it was used as the independent variable to produce the residuals for characters regressed against it. Certain variables were removed because they obvious- ly replicate the same measurement. That is, characters ILL (5) and ILR (6) refer to the number of infralabials on the left and right side of the head, and characters TML (11) and TMR (12) refer to the number of temporals on the left and right side of the head. Only the characters taken on the left side of the head were used (ILL and

i-*


201IEPTLGCLMNGAH

Q P%o e o 0(?

0

1000 SV (mm)

1500

FIG. 8.-Graph of HL/SV against SV for all samples of Elaphe obsoleta. Arrow indicates where the change in HL/SV begins to diminish.

TML). Also, the following color measurements were eliminated from the DFA because they may be replicating other characters or appear in so few snakes that they would severely limit the number of specimens used in Case 3: 18, 20, 22, 24, 26, 27, 28, 29, and 30.

Standardized measurements were used to discuss differences between clades in a practical sense. Therefore, HL and TL were divided by SV, and all head measurements were divided by HL. These ratios were not used in any statistical analyses.

RESULTS

Significant sexual dimorphism (P < 0.05) was observed in the following characters: eastern clade = 1, 19, 33, 34, 36, 37, 39, 40-43, 45-47, 49, 50-52, 56-58, 60-64, 66, and 67; central clade = 2, 5, 6, 13-15, 17, 31, 33-41, 43-47, 49-52, 54- 58, and 61-67; western clade = 1, 2, 15, 17, 18, 33, 34, 36-38, 41, 44, 45, 49, 54- 57, 61, 62, and 65-67; E. bairdi - 2 and 21. Characters in males tended to be larger than characters in females except for the following: eastern clade = 1 and 19;

central clade = 5, 6, and 14; western clade = 1 and 15. The results of the ANOVAs between clades for each character considering the sexes separately are displayed in Tables 1 and 2. In males, 83.6% of the raw characters examined univariately differed significantly among clades. In females, 80.3% of the raw characters examined univariately differed significantly among clades. For males, the following characters had F-ratio values higher than 5.0 and were included in DFA for Case 4: 1, 2, 5, 13-17, 19, 21, 23, 25, 29-32, 35-38, 40- 45, 47-49, 51, 52, 54, 55, 57, 59, 61-67. For females, the following characters had F-ratio values higher than 5.0 and were included in the DFA for Case 4: 1, 2, 5, 11, 13-17, 19, 21, 23, 25, 30-33, 36-38, 40- 42, 43-45, 47-49, 51, 52, 54, 57, 58, 61, 63-65. Only characters with F-ratio values higher than 5.0 for both males and females were used in the combined male and female data set in the DFA for Case 4.

The between groups F- matrix from the DFA showed significant differences between all four molecular clades for all Cas- es using male and female data separately

0.06

0.05 00 0 Cm

(0

-j Ir

0.04

0.03

0020 500 2000

~7 r i I I

9 2001] HERPETOLOGICAL MONOGRAPHS

TABLE 1.-Results of ANOVAs performed on raw variables for males for the four clades of rat snakes. Character abbreviations follow the format in Table 2.1. Clades are abbreviated as follows: E = Eastern, C = Central, W = Western, and B = E. bairdi. The degree of significant difference between clades and the selected clade row is indicated by * (0.01 < P < 0.05), ** (0.001 < P < 0.01), and *** (P < 0.001). F-Ratio (F), number of specimens used for each character (n), mean of each character (mean), minimum character value (Min), maximum character value (Max), and standard deviation (SD) are reported for each clade.

N.A. indicates that the character was not applicable for that clade and n.s. indicates no significant difference exists between selected clades.

Ventrals Subcaudals ILL ILR TML TMR SV TL Clade F 71.637 70.442 130.091 178.862 40.547 22.562 1.015 3.530

E n 237 150 236 231 226 226 238 152 Mean 232.941 89.147 11.436 11.385 8.951 8.885 1092.16 242.105 Min 221 72 10 10 3 5 602 145 Max 243 99 13 13 15 14 1750 355 SD 3.917 5.694 0.646 0.570 1.494 1.610 245.425 42.483 P W***, B*** C***, W***, B*** W***, B*** W***, B*** W***, B*** W***, B** n.s. W*

C n 163 126 163 161 170 170 164 131 Mean 231.785 82.175 11.509 11.540 8.988 8.959 1097.439 228.748 Min 220 65 10 10 4 5 610 136 Max 251 96 13 14 15 13 1620 345 SD 5.877 5.055 0.651 0.707 1.499 1.536 215.623 41.340 P W***, B*** E***, B*** W***, B*** W***, B*** W***, B*** W***, B*** n.s. n.s.

W n 144 91 144 144 143 143 144 90 Mean 229.403 82.769 12.736 12.861 10.406 10.427 1078.951 224.933 Min 213 63 11 11 6 6 610 110 Max 242 92 15 14 17 19 1649 380 SD 4.852 4.672 0.908 0.890 1.944 2.256 211.11 45.090 P E***, C***, B*** E***, B*** E***, C***, B*** E***, C***, B*** E***, C***, B*** E***, C*** n.s. E*

B n 18 14 18 18 17 17 18 14 Mean 246.944 96.286 13.278 13.667 12.294 11.412 1004.111 236.643 Min 234 91 11 12 9 7 675 175 Max 256 104 14 15 18 16 1360 285 SD 7.312 3.583 0.9895 0.767 2.365 2.717 194.569 32.979 P E***, C***, W*** E***, C***, W*** E***, C***, W*** E***, C***, W*** E***, C***, W*** E**, C*** n.s. n.s.

0

Hm

z 0 0-1

(I

TABLE 1. Continued.

PW 13.756

PWP 5.662

234 7.993 4.95 12.49 1.434 W***

163 8.08 5.35 12.91 1.383 W***

234 7.761 5.12 11.13 1.285 W***, B**

162 7.913 5.66 11.17 1.209 W*, B***

142 8.978 5.82 13.6 1.54 E***, C***, B**

18 7.765 5.72 10.61 1.371 W**

144 8.349 5.34 11.76 1.297 E***, C*, B***

18 6.564 5.14 8.93 1.055 E**, C***, W***

233 3.247 1.89 5.27 0.63 B***

162 3.214 2.0 5.020 0.613 B**

142 3.228 1.81 4.67 0.6 B**

235 8.329 5.46 12.02 1.231 W*

162 8.334 6.06 12.12 1.189 n.s.

144 8.688 4.24 12.13 1.271 E*

18 2.618 1.74 5.36 0.868 E***, C**, W**

18 8.107 6.45 10.45 1.013 n.s.

235 5.082 3.32 7.72 0.798 W***

162 5.237 3.58 9.5 0.881 W*, B*

144 5.518 3.61 7.53 0.880 E***, C*, B***

18 4.575 3.25 6.11 0.73 C*, W***

234 4.545 2.46 6.46 0.662 W***

162 4.723 2.61 7.65 0.803 W*, B**

144 4.95 2.87 6.92 0.816 E***, C*, B***

18 4.122 2.84 5.16 0.657 C**, W***

Clade HL

F 8.736 PL

15.866 FL

3.393 FW

11.641 FWP

12.382

E n Mean Min Max SD P

C n Mean Min Max SD

W n Mean Min Max SD P

B n Mean Min Max SD p

237 37.137 22.57 54.44 6.672 W**

164 36.846 23.190 56.860 6.068 W**

143 39.752 26.24 52.82 6.597 E**, C**, B**

18 33.62 24.59 48.14 5.689 W**

H

~z 0- 0T

TABLE 1.-Continued.

FWA PRFL PRFWA PRFWP INL INWA INWP EYE Clade F 15.525 13.774 14.244 23.843 2.024 10.6 15.109 9.509

E n 235 231 231 234 221 220 222 233 Mean 7.013 5.861 5.652 4.227 2.634 4.459 3.909 5.279 Min 4.7 3.11 3.28 2.51 1.14 1.870 2.070 3.25 Max 10.15 8.97 8.43 6.65 4.64 7.19 6.62 7.74 SD 7.013 1.078 1.086 0.768 0.631 0.879 0.806 0.703 P W***, B* W***, B* W***, B*** C**, W***, B** n.s. W**, B** W***, B** W***

C n 162 157 157 160 150 148 152 162 Mean 6.946 5.911 5.913 4.502 2.5 4.618 4.031 5.452 Min 4.69 2.05 3.71 2.61 1.2 2.95 1.24 3.67 Max 9.99 8.92 8.34 7.31 5.45 6.46 6.47 7.53 SD 1.023 1.116 1.01 0.818 0.619 0.794 0.783 0.696 P W*** W***, B* B*** E**, W**, B*** n.s. B*** W*, B*** B*

W n 144 142 142 143 134 133 137 143 Mean 7.611 6.462 6.119 4.806 2.479 4.776 4.321 5.613 Min 4.9 4.05 3.52 2.89 1.08 2.57 2.44 3.95 Max 10.29 9.32 8.41 6.65 7.78 6.67 6.65 7.23 SD 1.152 1.175 1.027 0.814 0.749 0.842 0.81 0.682 P E***, C***, B*** E***, C***, B*** B*** E***, C**, B*** n.s. E**, B*** E***, C*, B*** E***, B**

B n 18 17 18 18 16 17 18 18 Mean 6.311 5.073 4.608 3.547 2.579 3.67 3.149 4.961 Min 4.62 3.69 2.67 2.47 1.65 2.57 2.11 3.75 Max 8.31 6.18 6.53 5.17 3.35 5.16 4.96 6.38 SD 0.993 0.714 1.055 0.642 2.579 0.643 0.713 0.705 P E*, W*** E*, C*, W*** E**, C***, W*** E**, C***, W*** n.s. E**, C***, W*** E**, C***, W*** C*, W**

z

H

0

0

cr

toO

TABLE 1.-Continued.

AG PG INR NR RH RW PNL ANL Clade F 1.662 5.588 16.954 2.316 21.235 9.865 2.701 11.439

E n 231 Mean 9.619 Min 5.94 Max 14.64 SD 1.851 P n.s.

C n 161 Mean 9.434 Min 5.47 Max 13.39 SD 1.598 P n.s.

W n 144 Mean 9.823 Min 6.25 Max 13.69 SD 1.642 P n.s.

B n 18 Mean 9.183 Min 6.6 Max 13.28 SD 1.749 P n.s.

228 4.278 2.51 7.33 0.909 W*, B***

156 4.449 2.69 7.05 0.826 B***

231 223 232 2.977 5.65 7.513 1.57 3.16 4.3 4.58 8.79 12.0 0.603 1.154 1.487 n.s. C***, W***, B** W*, B**

154 6.128 3.83 9.66 1.127 E***, B***

133 6.423 3.72 8.79 1.1 E***, B***

160 7.806 4.73 11.43 1.398 B***

156 3.081 1.63 4.61 0.59 n.s.

137 4.575 2.08 6.66 0.869 E*, B***

137 3.112 1.76 4.49 0.57 n.s.

232 2.243 1.27 3.52 0.481 n.s.

159 2.339 1.2 3.92 2.339 n.s.

143 7.978 5.08 10.91 1.376 E*, B***

143 2.218 1.22 3.38 0.466 n.s.

18 17 17 18 18 3.086 2.867 4.702 6.218 2.044 2.11 1.9 2.79 4.32 1.38 4.11 3.84 6.37 8.24 2.8 0.635 0.508 1.025 1.211 0.363 E***, C***, W*** n.s. E***, C***, B*** E**, C***, W*** n.s.

231 2.381 1.27 5.070 0.56 W***

z

0

C

0

0

It

159 2.517 1.56 4.0 0.541 W**

143 2.693 1.37 4.23 0.869 E***, C**, B**

18 2.166 1.49 3.48 0.442 W**

231 9.266 5.65 15.73 1.986 B**

159 2.517 1.56 4.0 0.541 B*

141 9.448 4.99 14.37 1.945 B**

17 7.59 2.98 11.47 2.021 E**, C*, W**

TABLE 1.-Continued.

PROW PROLD PROLV LD LV LHT LL LH Clade F 9.865 1.887 0.307 13.846 5.648 9.049 8.056 7.804

E n 235 235 235 234 235 235 234 232 Mean 4.697 3.127 2.188 2.087 3.177 1.909 28.682 4.828 Min 2.85 1.48 1.14 1.15 1.18 0.990 18.9 2.57 Max 7.56 5.24 3.86 3.78 5.48 3.35 42.24 7.59 SD 0.835 0.672 0.523 0.478 0.673 0.424 5.133 1.048 P n.s. n.s. n.s. W*** W** W** W** B***

C n 161 161 161 160 160 160 161 162 Mean 4.838 3.057 2.146 2.027 3.173 2.005 28.662 4.873 Min 3.25 1.82 1.27 1.06 2.09 1.18 19.81 2.58 Max 7.31 4.96 5.18 3.23 4.71 4.06 40.29 7.92 SD 0.789 0.618 0.509 0.45 0.593 0.443 4.48 0.952 P B** n.s. n.s. W*** W** B** W** B***

W n 143 143 143 142 143 143 143 142 Mean 4.932 2.971 2.186 2.371 3.42 2.064 30.581 4.827 Min 3.08 1.76 1.02 0.99 1.82 1.15 20.63 2.27 Max 7.04 4.57 3.57 5.65 5.08 3.37 40.12 7.050 SD 0.829 0.585 0.492 0.601 0.651 0.434 4.814 0.99 P B** n.s. n.s. E***, C*** E**, C** E**, B*** E**, C**, B** B***

B n 18 18 18 18 18 18 18 18 Mean 4.178 2.993 2.125 2.044 3.049 1.588 25.904 3.692 Min 3.22 2.29 1.53 1.38 2.32 1.15 18.81 2.36 Max 4.85 4.45 3.17 2.82 3.88 2.2 37.96 5.27 SD 0.464 0.566 0.445 0.372 0.473 0.267 4.539 0.714 P C**, W** n.s. n.s. n.s. n.s. C**, W*** W** E***, C***, W***

H 0

~z

0

TABLE 1.-Continued.

DSR10 DSR50 DSRPEN DSR1 VR K DB LB Clade F 52.931 15.370 19.654 19.654 3.344 65.499 100.469 15.076

E n 233 236 227 235 235 238 136 52 Mean 26.086 25.903 18.855 6.02 5.598 3.571 34.993 36.75 Min 23.0 21.0 16.0 3.21 3.04 2.0 25.0 9.0 Max 29.0 29.0 23.0 9.8 9.08 7.0 45.0 50.0 SD 1.047 1.609 0.729 1.454 1.283 0.882 4.421 6.919 P C***, W***, B*** C*, W*** B* B* B* B*** C***, W***, B*** C*, W**, B***

C n 160 162 160 162 161 162 132 47 Mean 25.588 25.457 18.812 6.13 5.676 3.377 30.523 33.638 Min 23.0 19.0 14.0 3.6 3.33 2.0 26.0 28.0 Max 29.0 29.0 22.0 9.21 8.18 6.0 40.0 42.0 SD 1.006 1.565 0.877 1.19 1.105 0.748 2.923 3.892 P E***, W***, B*** E*, W*** B** B** B* B*** E***, B*** E*, B***

W n 141 144 139 144 144 143 102 64 Mean 27.085 26.618 19.36 6.157 5.605 3.329 31.353 33.32 Min 23.0 23.0 17.0 3.35 3.11 2.0 25.0 13.5 Max 31.0 30.0 22.0 9.09 8.52 6.0 41.0 46.0 SD 1.417 1.394 0.885 1.355 1.134 0.776 2.713 4.525 P E***, C*** E***, W*** B** B** B* B*** E***, B*** E**, B***

B n 18 18 17 18 18 18 2 1 Mean 27.667 26.44 19.824 5.043 4.742 6.278 66.5 64.0 Min 25.0 23.0 19.0 3.46 3.46 4.0 58.0 64.0 Max 29.0 28.0 21.0 6.8 6.55 11.0 75.0 64.0 SD 1.372 1.199 0.941 0.935 1.011 1.776 12.021 P E***, C*** n.s. E*, C**, W** E*, C**, W*** E*, C*, W* E***, C***, W*** E***, C***, W*** E***, C***, W***

H

0 z-1 0 0

TABLE 1.-Continued.

DBW1 DBW2 DBL1 DBL2 LBW1 LBW2 LBL1 LBL2 Clade F 108.171 12.165 53.743 15.294 39.559 2.781 26.172 1.443

E n 140 119 159 157 96 89 84 78 Mean 10.596 6.345 4.912 4.188 4.531 2.382 3.33 1.590 Min 5.0 3.0 2.0 1.0 1.5 1.0 1.0 1.0 Max 15.0 9.0 11.0 23.0 7.0 12.0 7.0 5.0 SD 1.454 0.972 1.514 2.281 1.353 3.133 1.311 1.012 P C***, W***, B* W*** C***, W***, B*** C***, W*** C**, W*** n.s. C***, W***, B* n.s.

C n 107 97 124 119 78 67 73 69 Mean 12.86 6.381 5.433 5.433 5.276 1.642 4.377 1.594 Min 9.0 5.0 3.0 2.0 3.0 1.0 1.0 1.0 Max 17.0 10.0 10.0 8.5 8.0 10.0 7.0 5.0 SD 1.632 1.035 1.007 1.045 1.116 1.632 1.312 1.312 P E***, W***, B*** W*** E***, B*** E***, B** E**, W*** n.s. E***, B*** n.s.

W n 93 92 108 108 84 82 84 82 Mean 14.355 7.082 6.088 5.361 6.625 1.567 4.732 1.366 Min 7.0 5.0 4.5 3.5 1.0 1.0 1.0 1.0 Max 19.0 9.0 9.0 8.0 9.0 4.0 8.0 6.0 SD 1.608 0.881 0.891 0.840 1.364 0.898 1.107 0.824 P E***, C***, B*** E***, C*** E***, B*** E***, B** E***, C***, B* n.s. E***, B*** n.s.

B n 5 2 7 5 4 3 6 4 Mean 8.2 6.0 2.143 2.2 4.75 2.333 1.833 1.0 Min 3.0 5.0 1.0 2.0 3.0 1.0 1.0 1.0 Max 10.0 7.0 3.0 3.0 7.0 3.0 2.0 1.0 SD 2.95 1.414 2.95 0.447 2.062 1.155 0.408 0 P E***, C***, W*** n.s. E***, C***, W*** C**, W** W* n.s. E*, C***, W*** n.s.

H 0

~z 0 0

TABLE 1.-Continued.

DSW LSW VBLAT VBMED SLBN ILBN

Clade F 0.231 4.375 12.349 8.236 5.699 7.355

E n 109 107 214 195 187 187

Mean 2.096 3.047 15.598 35.518 5.267 8.326

Min 1.5 1.5 0.0 0.0 0.0 0.0

Max 3.5 4.0 159.0 156.0 9.0 13.0

SD 0.405 0.443 29.569 40.585 1.821 3.36

P n.s. B* C***, W*** W*, B*** W* W***

n N.A. N.A. 161 163 161 158

Mean N.A. N.A. 6.261 29.877 5.323 8.228

Min N.A. N.A. 2.0 1.0 0.0 0.0

Max N.A. N.A. 17.0 120.0 8.0 13.0

SD N.A. N.A. 2.551 20.175 1.503 2.762

P N.A. N.A. E*** B** C** W**

W n N.A. N.A. 141 140 136 131

Mean N.A. N.A. 4.922 23.698 4.625 6.634

Min N.A. N.A. 1.000 1.0 0.0 0.0

Max N.A. N.A. 10.0 154.0 8.0 14.0

SD N.A. N.A. 1.761 23.698 2.055 4.201

P N.A. N.A. E*** E*, B* E*, C** E***, C**

B n 13 13 17 18 16 16

Mean 2.154 2.769 3.824 2.0 4.25 7.937

Min 1.5 2.0 2.0 0.0 0.0 0.0

Max 3.0 3.5 6.0 5.0 6.0 13.0

SD 0.427 0.525 1.185 2.0 1.915 3.511

P n.s. B* n.s. E***, C**, W* n.s. n.s.

H 0

z

0)

--I -.1

TABLE 2.-Results of ANOVAs performed on raw variables for females for the four clades of rat snakes. Character abbreviations follow the format in Table 2.1. Clades are abbreviated as follows: E = Eastern, C = Central, W = Western, and B = E. bairdi. The degree of significant difference between clades and the selected clade row is indicated by * (0.01 < P < 0.05), ** (0.001 < P < 0.01), and *** (P < 0.001). F-Ratio (F), number of specimens used for each character (n), mean of each character (mean), minimum character value (Min), maximum character value (Max), and standard deviation (SD) are reported for each clade.

N.A. indicates that the character was not applicable for that clade and n.s. indicates no significant difference exists between selected clades.

Ventrals Subcaudals ILL ILR TML TMR SV TL Clade F 32.695 30.522 59.503 59.407 32.838 20.918 0.890 4.194

E n 148 84 146 143 146 148 148 84 Mean 236.115 82.071 11.521 11.517 8.904 9.048 1020.0 213.310 Min 226.0 70.0 8.0 8.0 6.0 4.0 610.0 130.0 Max 249.0 96.0 13.0 13.0 14.0 15.0 1520.0 327.0 SD 4.324 5.542 0.735 0.749 1.739 1.775 185.815 40.160 P W***, B*** C***, W***, B** W***, B*** W***, B*** W***, B*** W***, B*** n.s. C**, W*

C n 126 101 125 123 124 126 126 102 Mean 235.849 76.228 11.776 11.797 9.137 9.194 1006.889 195.941 Min 223.0 60.0 10.0 10.0 6.0 5.0 604.0 70.0 Max 226.0 89.0 14.0 14.0 15.0 14.0 1473.0 280.0 SD 5.817 5.028 0.761 0.849 1.679 1.991 163.605 29.755 P W***, B*** E***, B**** W***, B**** W***, B*** W***, B*** W***, B*** n.s. E**

W n 85 60 85 83 85 84 85 60 Mean 231.388 77.617 12.76 12.831 10.788 10.702 1002.365 196.517 Min 220.0 70.0 10.0 10.0 7.0 6.0 610.0 125.0 Max 242.0 94.0 15.0 15.0 16.0 18.0 1560.0 261.0 SD 5.178 4.574 0.924 0.881 2.199 2.194 184.386 32.9 P E***, C***, B*** E***, B*** E***, C***, B*** E***, C***, B*** E***, C***, B** E***, C*** n.s. E*

B n 9 0 9 9 9 9 9 8 Mean 246.33 88.125 13.889 13.667 13.222 11.89 926.889 208.25 Min 238.0 85.0 13.0 12.0 11.0 9.0 642.0 153.0 Max 259.0 94.0 15.0 15.0 16.0 15.0 1130.0 250.0 SD 5.723 3.091 0.928 0.494 1.856 2.088 153.626 30.658 P E***, C***, W*** E**, C***, W*** E***, C***, W*** E***, C***, W*** E***, C***, W** E***, C*** n.s. n.s.

H

0 z-1 0

0

TABLE 2.-Continued.

HL PL PW PWP FL FW FWP FWA Clade F 9.54 8.609 10.733 7.521 4.82 12.313 10.861 11.342

E n 148 145 147 144 147 147 147 146 Mean 35.994 7.454 7.473 3.182 7.966 4.83 4.245 6.792 Min 23.14 5.19 4.7 1.77 4.29 3.26 2.84 4.08 Max 50.58 12.17 10.73 4.98 10.96 7.18 6.38 9.56 SD 5.366 1.187 1.116 0.583 1.061 0.668 0.595 0.965 P W*, B* W*** W**, B*** B*** W** W*** W*** W***, B*

C n 126 126 126 126 126 126 126 125 Mean 34.77 7.528 7.549 3.059 7.968 4.933 4.435 6.761 Min 21.030 4.94 5.32 1.86 5.6 3.48 3.04 4.54 Max 45.63 11.23 10.03 4.58 10.64 7.17 7.06 8.93 SD 5.0 1.15 1.005 0.553 0.922 0.712 0.676 0.888 P W*** W*** W*, B*** B** W* W** B** W***, B*

W n 85 84 85 84 85 85 84 84 Mean 38.182 8.227 7.969 3.031 8.421 5.322 4.667 7.347 Min 26.95 5.74 5.54 2.03 6.09 3.79 2.54 4.03 Max 49.82 12.24 10.79 4.51 10.86 7.1 6.69 9.45 SD 5.621 1.287 1.126 0.494 1.091 0.785 0.759 1.04 P E*, C***, B** E***, C*** E**, C*, B*** B** E**, C* E***, C**, B*** E***, B*** E***, C***, B***

B n 9 9 9 9 9 9 9 9 Mean 31.231 7.239 6.004 2.331 7.642 4.224 3.677 5.834 Min 22.57 5.54 5.06 1.82 6.5 3.06 2.8 4.78 Max 37.4 8.82 6.9 2.84 9.26 4.9 4.53 7.45 SD 4.295 0.995 0.549 0.362 0.876 0.553 0.615 0.844 P E*, W*** n.s. E***, C***, W*** E***, C**, W** n.s. C*, W*** C**, W*** E*, C*, B***

H 0

z 0

TABLE 2.-Continued.

PRFL PRFWA PRFWP INL INWA INWP EYE AG Clade F 10.106 7.659 10.309 2.099 10.934 11.830 6.02 2.55

E n 144 141 144 133 133 137 146 146 Mean 5.612 5.456 4.071 2.457 4.24 3.777 5.032 9.106 Min 3.61 3.45 2.24 1.14 2.73 2.23 3.84 5.5 Max 8.04 7.56 5.85 4.08 6.43 6.13 6.25 12.67 SD 0.919 50.89 0.624 0.591 0.746 0.689 0.511 1.528 P W*** W*, B** C*, W*** n.s. W**, B*** W**, B** W** n.s.

C n 122 122 122 115 115 118 125 124 Mean 5.662 5.613 4.307 2.327 4.336 3.9 5.147 8.913 Min 3.88 3.06 2.89 1.11 2.17 2.0 2.96 5.67 Max 8.58 8.26 8.12 3.91 6.08 5.73 6.49 13.34 SD 0.886 0.907 0.779 0.554 2.724 0.67 0.616 1.398 P W** W*, B** E*, B* n.s. B*** B*** n.s. n.s.

W n 81 82 83 77 77 79 85 82 Mean 6.185 5.806 4.527 2.323 4.585 4.153 5.319 9.409 Min 4.04 4.03 2.65 1.21 3.34 2.69 4.07 6.53 Max 8.21 7.9 6.15 3.27 6.11 5.64 6.88 12.93 SD 1.011 0.883 0.678 0.456 0.627 0.713 0.634 1.46 P E***, C**, B*** E**, C***, B** E***, B** n.s. E**, B*** E**, B*** E**, B* n.s.

B n 9 9 9 9 9 9 9 9 Mean 4.872 4.437 3.613 2.497 3.236 2.868 4.703 8.413 Min 3.73 3.57 2.33 2.15 1.35 1.95 4.08 6.04 Max 5.74 5.61 4.93 2.99 4.22 3.46 5.69 10.12 SD 0.665 0.643 0.792 0.33 0.893 0.481 0.498 1.332 P W*** E*, B*** E**, C**, W*** n.s. E***, C***, W*** E**, C***, W*** W* n.s.

0

H 0

0 C)1 C)

0 z

0 0

TABLE 2.-Continued.

PG INR NR RH RW PNL ANL PROW Clade F 7.041 13.228 1.175 12.554 4.393 1.041 7.05 6.62

E n 146 140 143 133 145 147 147 147 Mean 8.779 3.987 2.981 5.45 7.195 2.041 2.26 4.522 Min 5.56 2.46 1.71 3.14 4.45 1.15 1.33 2.63 Max 12.65 5.92 6.07 8.62 10.42 2.96 3.65 6.5 SD 1.643 0.755 0.647 0.999 1.256 0.37 0.463 0.702 P B*** W*, B*** n.s. C*, W***, B* B* n.s. W** W*, B*

C n 124 123 121 119 123 123 123 123 Mean 8.54 4.127 2.95 5.831 7.265 2.078 2.387 4.571 Min 4.99 2.51 1.89 3.88 4.66 1.2 1.21 2.97 Max 12.71 5.95 4.21 8.62 10.96 3.18 3.43 6.01 SD 1.492 0.76 0.544 1.003 1.178 2.078 0.425 0.676 P B** W***, B**** n.s. E*, B*** B* n.s. B* B*

W n 83 81 81 76 81 81 82 84 Mean 8.938 4.318 3.084 6.064 7.46 2.059 2.491 4.792 Min 4.69 2.84 1.88 4.0 4.98 1.18 1.46 3.01 Max 12.36 6.67 6.34 7.67 9.99 2.92 3.45 7.06 SD 1.728 0.787 0.604 0.901 1.147 0.404 0.484 0.694 P B*** E***, C***, B*** n.s. E***, B*** B** n.s. E**, B** E*, B***

B n 9 8 9 9 9 9 9 9 Mean 6.427 88.125 2.796 4.397 5.964 1.849 1.968 3.822 Min 3.93 85.0 2.09 2.98 4.53 1.54 1.72 2.84 Max 9.25 94.0 3.11 5.14 7.29 2.34 2.31 4.68 SD 1.702 3.091 0.342 0.658 0.9 0.275 0.204 0.513 P E***, C**, W*** E**, C***, W*** n.s. E*, C***, W*** E*, C*, W** n.s. C*, W** E*, C*, W***

z

0

~z 0'l 0

TABLE 2.-Continued.

PROLD PROLV F 0.412 1.243

LD 11.498

147 1.738 1.04 2.75 0.344 W***

122 1.822 1.01 2.77 1.822 W**

147 27.401 18.58 39.77 4.002 W**

126 27.161 17.85 37.12 3.841 W***

83 1.99 1.32 2.7 0.322 E***, C**, B**

9 1.58 1.3 1.83 0.185 W**

147 4.691 2.66 7.55 0.991 B***

126 4.592 1.69 7.49 0.848 B***

83 29.506 20.7 40.08 29.506 E**, C***, B**

9 24.081 17.4 29.38 3.461 W**

141 26.206 21.0 29.0 1.198 W***, B***

123 26.13 25.0 29.0 1.166 W***, B***

83 4.556 2.93 6.95 0.74 B***

9 3.302 2.69 4.17 0.499 E***, C***, W***

83 27.337 25.0 31.0 1.364 E***, C***, B*

9 28.556 27.0 29.0 0.726 E***, C***, W*

Clade LV

4.214 LHT

11.682 LL

9.178 LH

7.107 DSR10 28.064

E n Mean Min Max SD P

C n Mean Min Max SD P

W n Mean Min Max SD P

B n Mean Min Max SD P

147 3.038 1.93 4.64 0.564 n.s.

123 3.006 1.75 4.46 0.546 n.s.

83 2.966 1.75 5.24 0.583 n.s.

9 2.899 2.29 3.64 0.451 n.s.

147 2.081 1.15 3.24 0.416 n.s.

123 2.063 1.22 3.16 0.403 n.s.

83 2.161 1.15 3.31 0.419 n.s.

9 1.983 1.68 2.45 0.25 n.s.

146 1.907 1.14 3.38 0.388 W***

123 1.841 0.97 3.37 1.841 W***

83 2.167 1.36 3.63 0.436 E***, C***

9 2.011 1.29 2.44 0.361 n.s.

147 3.012 1.79 4.69 0.566 W*

123 2.999 1.97 4.53 0.596 W**

83 3.252 2.36 4.24 0.466 E*, C**

9 3.143 2.19 4.19 0.557 n.s.

H 0

0 0--

TABLE 2.-Continued.

DSR50 DSRPEN DSR1 VR K DB LB DBW1 Clade F 7.945 10.924 2.394 1.899 34.806 47.561 20.864 29.478

E n 148 146 148 148 148 86 31 83 Mean 25.919 19.253 5.518 5.069 3.716 35.035 36.129 11.584 Min 22.0 17.0 3.14 2.94 2.0 10.0 14.0 7.0 Max 29.0 22.0 8.47 7.00 7.0 47.0 48.0 17.0 SD 1.505 0.768 1.085 0.957 0.896 5.365 6.884 1.707 P W** W***, B** n.s. n.s. C*, W*, B*** C***, W***, B*** C*, W***, B*** C***, W***

C n 126 124 126 126 126 97 46 87 Mean 25.643 19.315 5.555 5.083 3.444 29.763 32.63 13.218 Min 21.0 16.0 3.12 2.67 2.0 25.0 24.0 9.0 Max 29.0 19.0 7.87 7.35 5.0 38.0 40.0 20.0 SD 1.642 0.837 1.006 0.922 0.722 2.528 3.641 1.748 P W*** W***, B** n.s. n.s. E*, B*** E***, B*** E*, B*** E***, W**, B*

W n 85 85 85 85 85 66 41 58 Mean 26.624 19.718 5.626 5.125 3.4 30.439 31.195 14.302 Min 23.0 19.0 3.17 2.97 2.0 25.0 14.0 6.0 Max 30.0 23.0 9.02 7.26 5.0 47.0 40.0 17.0 SD 1.291 0.921 1.091 0.925 0.694 3.104 4.155 2.096 P E**, C*** E**, C*** B* n.s. E*, B*** E***, B*** E***, B*** E***, C**, B***

B n 9 9 9 9 9 9 2 3 Mean 26.67 20.333 4.64 4.344 6.333 51.0 56.0 9.833 Min 23.0 19.0 3.39 2.89 4.0 46.0 52.0 8.5 Max 28.0 21.0 6.31 6.08 11.0 56.0 60.0 11.0 SD 1.414 1.0 0.852 0.959 2.236 7.071 5.657 1.258 P n.s. E**, C** W* n.s. E***, C***, W*** E***, C***, W*** E***, C***, W*** C*, W***

H

0 0

TABLE 2.-Continued.

DBW2 DBL1 DBL2 LBW1 LBW2 LBL1 LBL2 DSW Clade F 13.717 32.185 21.030 24.869 5.513 28.622 1.325 5.711

E n 82 103 101 55 54 48 46 77 Mean 6.189 4.903 4.149 4.573 2.602 2.948 1.402 2.039 Min 3.0 2.0 2.0 2.0 1.0 1.0 1.0 1.0 Max 8.0 13.0 13.0 8.0 13.0 6.0 5.0 3.0 SD 1.002 1.657 2.115 1.292 3.33 1.213 0.8 0.322 P C*, W*** C***, W*** C***, W*** C*, W*** C* C***, W*** n.s. B*

C n 75 95 92 69 59 68 61 N.A. Mean 6.593 6.416 5.679 5.254 1.432 4.838 1.689 N.A. Min 5.0 4.5 3.5 1.5 1.0 2.0 1.0 N.A. Max 9.0 8.0 7.5 8.0 3.0 10.0 9.0 N.A. SD 0.725 0.859 0.913 1.215 0.626 1.48 1.232 N.A. P E*, W** E***, B*** E***, B** E*, W*** E*, B* E***, B*** n.s. N.A.

W n 58 85 68 54 54 54 52 N.A. Mean 7.181 6.154 5.36 6.806 1.611 4.787 1.337 N.A. Min 5.0 4.0 3.0 3.5 1.0 2.0 1.0 N.A. Max 10.0 8.0 7.0 14.0 5.0 8.0 7.0 N.A. SD 0.911 0.959 0.918 1.669 0.839 1.16 0.901 N.A. P E***, C** E***, B*** E***, B* E***, C*** n.s. E***, B*** n.s. N.A.

B n 3 3 3 4 4 4 3 3 Mean 6.5 3.0 2.667 5.25 4.25 1.75 1.667 2.5 Min 5.0 3.0 2.5 4.0 1.0 1.0 1.0 2.0 Max 8.5 3.0 3.0 7.0 7.0 2.0 2.0 3.0 SD 1.803 0.0 0.289 1.258 2.5 0.5 0.557 0.5 P n.s. C***, W*** C**, W* n.s. C* C***, W*** n.s. E*

NO

z

C)

0

TABLE 2.-Continued.

LSW VBLAT VBMED SLBN ILBN Clade F 0.099 9.956 5.471 0.579 5.513

E n 76 135 125 116 116 Mean 3.059 14.874 33.712 5284 8.526 Min 1.5 0.0 0.0 0.0 0.0 Max 3.5 120.0 160.0 9.0 13.0 SD 0.346 25.976 41.007 1.570 8.526 P n.s. C***, W*** W*, B** n.s. n.s.

C n N.A. 126 126 122 120 Mean N.A. 5.563 26.762 5.189 7.775 Min N.A. 0.0 3.0 0.0 0.0 Max N.A. 18.0 66.0 7.0 13.0 SD N.A. 2.451 15.173 1.801 3.066 P N.A. E*** n.s. n.s. n.s.

W n N.A. 80 68 84 82 Mean N.A. 21.825 5.36 5.036 7.476 Min N.A. 0.0 3.0 0.0 0.0 Max N.A. 120.0 7.0 8.0 13.0 SD N.A. 23.857 0.918 1.917 4.143 P N.A. E*** E* n.s. n.s.

B n 4 9 3 9 9 Mean 3.0 4.222 1.0 4.667 9.667 Min 2.0 2.0 0.0 1.0 5.0 Max 3.5 7.0 3.0 7.0 15.0 SD 0.707 1.641 1.323 1.871 3.606 P n.s. n.s. E** n.s. n.s.

H 0

0 z) 0

0


U4

2

-42\

-2 0 8

* Eastern Clade o Central Clade v Western Clade v Elaphe bairdi

FIG. 9.-Three dimensional plot of the first three discriminant function scores based on all Case 3 variables for males.

or combined (P < 0.001). Wilks Lambda demonstrated that there was significant dispersion among all of the molecular clades for all Cases using male and female data separately or combined (P < 0.001). Although the three clades of E. obsoleta appear to be grouped closely on these scatterplots, each clade still occupies its own morphospace (Figs. 9, 10). The res- olution between clades is clearest for all Case 3 and Case 4 variables and for male and female data analyzed separately. This may indicate that color measurements along with other morphological characters are important for distinguishing clade differences.

Although less clear, separation between

all clades is also demonstrated with PCA (Figs. 11, 12). Using ANOVA with a Bon- ferroni adjustment, all clades were significantly different at P < 0.001 on either the first or second principal component axis. Both male and female data revealed that all clades were significantly different except the eastern and western clade on the first principal component axis. However, for males alone and the combined-sex data, ANOVA performed on the second principal component axis revealed that all clades were significantly different. All clades except the eastern and central groups were significantly different for females on the second principal component axis. Significant differences exist between



LL

d' / -15 "

-6 /-20

4y

2- 0-2 ' -6- 6 - /-325

O,22 -10 -35

* Eastern Clade o Central Clade T Western Clade v Elaphe bairdi

FIG. 10.-Three dimensional plot of the first three discriminant function scores based on all Case 3 variables for females.

all clades on the third principal component axis for females only and combined-sex data. The eastern and central clades were not significantly different on the third principal component for males. On the first PC axis, males and females had high loadings for the following mensural characters: RW (55), RH (54), INWP (48), PRFWA (44), and PW (37) (Tables 3, 4). The meristic characters, V (1) and SC (2), had the highest loadings on axis two for both males and females (Tables 3, 4).

Most characters had low (?0.01-0.9) or mid-ranged (?+ 1.0-4.0) discriminant functions (DF) (Tables 5, 6). Only a few characters had consistently high function values on the first axis for both males and females: LB (18), PROLD (59), and LD

(61). For males, the first axis describes 54.6% of the total variation DF variation, with AG (50), HL (35), TML (11), PROLD (59), LL (64), and LB (18) retaining the highest DF. This indicates that meristic, mensural, and color characters are all important in separating clades. For females, the first axis describes 55.4% of the total variation, with DB (17), DSR1 (66), VR (67), LB (18), and VBMED (32) retaining the highest DF.

Molecular clade classification matrices revealed that total classification scores for males, and females were very high (78- 100%) and were consistently higher for Case 3 and Case 4. The eastern and central clades had the lowest classification values (Tables 7, 8). This is consistent with



4 v

-\v

o Centra Clade

0

0 V v

0

2 0

3 2


FIG. 11.-Three dimensional plot of the scores for first three principal components based on all Case 2 variables for males.

the high overlap in eastern and central clade scores and the lower sequence di- vergences (Burbrink et al., 2000). Tables 9-10 show that classification matrices based on DFA for Case 2 variables that maximize separation between subspecies produced low total scores for males and females (59-67%). This is much lower than the total values for the DFA classification matrix on Case 2 variables for males and females when variation between clades is maximized (80-86%). The widest ranging subspecies, Elaphe o. obsoleta and E. o. lindheimeri, had the lowest classification scores. The insular form, E. o. deckerti produced the highest classification score (100%).

Because morphological overlap between

the eastern and central clades appears to be high (Figs. 9-12 and Tables 7, 8) sub- sequent analyses were performed that re- duced each clade into smaller populations (Fig. 13 and Table 11). Discriminant function analysis was performed to maximize separation between all populations and then examined to determine the spatial re- lationship of each population in light of the putative clade boundaries. Principal component scores were examined to insure that individual populations are homogeneous. Population boundaries were chosen according to general similarity in morphology, habitat, and collecting gaps. Visual inspection of the DF plots shows that the eastern and central clades are widely overlapped in the northern range


2001] HERPETOLOGICAL MONOGBAPHS 29

0 O v Ov:f cv o 0

D.. o 8=- eo

-2- "1 - ^' s2* d~.?

0X ' 0 -3


FIG. 12. Three dimensional plot of the scores for first three principal components based on all Case 2 variables for females.

of the eastern clade (Figs. 14, 15). Florida populations in the eastern clade appear to be relatively well separated from the central clade.

Ratios of mensural measurements are presented for males in Table 12 and females in Table 13. The ranges of most characters overlap even when corrected for size using proportional data.

DISCUSSION

The three molecular clades of Elaphe obsoleta and the fourth clade of E. bairdi can be distinguished morphologically using univariate and multivariate statistics.

The morphological groupings are concor- dant with the evolutionary lineages as revealed in the molecular analyses (Figs. 9- 12). The morphological classification matrices also support the separation of these molecular clades (Table 7, 8). The eastern and central clades are more closely related and are grouped more closely in morphological space. The western and E. bairdi clades are sister taxa and are most distantly related to the eastern and central clade (Fig. 2). However, E. bairdi is morphologically much more divergent from the eastern and central clades than the western clade (Figs. 9-11). The western



TABLE 3.-Principal component loadings for all Case TABLE 4.-Principal component loadings for all Case 2 variables for males. 2 variables for females.

Character Axis one Axis two Axis three Character Axis one Axis two Axis three

Ventrals -0.123 0.613 0.043 Ventrals -0.185 0.582 -0.073 Subcaudals -0.325 0.643 -0.094 Subcaudals -0.350 0.558 -0.077 ILLEFT -0.295 -0.067 0.672 ILLEFT -0.181 0.123 0.683 DSR10 -0.321 0.023 0.628 DSR10 -0.330 0.033 0.586 DSR50 -0.271 0.168 0.378 DSR50 -0.236 0.119 0.285 DSRPEN -0.208 0.121 0.486 DSRPEN -0.245 0.038 0.447 K -0.285 0.375 0.154 K -0.189 0.474 0.128 TL -0.341 0.415 -0.038 TL -0.332 0.362 -0.116 HL -0.582 -0.539 0.162 HL -0.545 -0.537 0.173 PL 0.304 0.138 0.396 PL 0.254 0.177 0.284 PW 0.704 0.021 0.180 PW 0.601 -0.025 0.098 PWP 0.377 0.076 -0.180 PWP 0.374 0.137 -0.180 FL 0.321 0.297 0.174 FL 0.265 0.032 0.245 FW 0.586 -0.138 0.207 FW 0.540 -0.216 0.237 FWP 0.402 -0.130 0.240 FWP 0.520 -0.232 0.227 FWA 0.525 -0.033 -0.357 FWA 0.556 -0.157 0.212 PRFL 0.265 -0.051 0.178 PRFL 0.567 -0.024 0.234 PRFWA 0.640 -0.377 -0.042 PRFWA 0.695 -0.187 -0.071 INL 0.200 0.430 -0.137 INL 0.497 -0.259 0.190 INWA 0.636 -0.167 -0.114 INWA 0.544 -0.364 -0.003 INWP 0.638 -0.378 0.062 INWP 0.644 -0.256 0.069 EYE 0.499 0.046 0.285 EYE 0.524 0.130 0.084 AG 0.305 0.347 -0.034 AG 0.420 0.241 -0.055 PG 0.146 0.151 -0.046 PG 0.257 0.007 -0.282 INR 0.440 -0.315 -0.211 INR 0.475 -0.274 -0.133 NR 0.493 0.040 0.067 NR 0.439 0.192 0.117 RH 0.617 -0.293 0.051 RH 0.702 -0.162 0.059 RW 0.717 -0.128 -0.069 RW 0.724 -0.056 -0.122 PNL 0.362 0.174 -0.177 PNL 0.436 0.156 -0.053 ANL 0.478 0.105 0.296 ANL 0.460 0.024 0.128 PROW 0.539 0.182 0.125 PROW 0.560 0.103 0.031 PROLD 0.208 0.529 -0.159 PROLD 0.419 0.675 -0.058 PROLV 0.227 0.456 0.039 PROLV 0.419 0.675 -0.058 LD 0.081 0.207 0.308 LD -0.075 0.136 0.470 LV 0.268 0.293 0.226 LV 0.109 0.298 0.443 LHT 0.477 0.076 0.101 LHT 0.516 0.108 0.347 LL 0.596 0.282 0.295 LL 0.584 0.179 0.224 LH 0.590 0.138 -0.168 LH 0.584 0.083 -0.325 DSR1 0.592 0.270 -0.249 DSR1 0.591 0.108 -0.066 VR 0.579 0.354 -0.180 VR 0.456 0.215 -0.074 TML -0.264 0.003 0.415 TML -0.218 -0.028 0.591

clade is more similar morphologically to xeric habitats of southwestern Texas and the eastern and central clades than to E. northeastern Mexico. Although these re- bairdi. Elaphe bairdi may be morpholog- cently diverged groups can be distin- ically distinctive because it has evolved in guished morphologically, the morphologi- an environment very different from that cal distance between groups may betray inhabited by the other clades. All mem- the actual evolutionary relationships of all bers of the eastern, central and western four clades as revealed by using mtDNA clades are found in wooded habitats of the (Fig. 2). eastern United States, whereas E. bairdi is DFA placed individuals into their mo- found in riparian habitats on the Edward's lecular clades much better than into their Plateau and xeric regions in southwest currently designated subspecies (Tables 7- Texas and northeastern Mexico (Schultz, 10). Difficulty arises in correctly identify- 1996). It is possible that E. bairdi evolved ing most subspecies. Most of these sub- its distinct morphology in response to the species could not be separated into groups



TABLE 5.-Canonical discriminant functions based TABLE 6.-Canonical discriminant functions based on all Case 3 variables for males. Values in parenthe- on all Case 3 variables for females. Variables in pa- ses represent the proportion of the sum of the eigen- rentheses represent the proportion of the sum of the

values. eigenvalues.

Axis

Character 1 (54.6%) 2 (32.0%) 3 (13.4%)

VENTRALS SUBCAUDALS ILLEFT DSR10 DSR50 DSRPEN K DB LB DBW DBL LBW LBL VBLAT VBMED TL HL PL PW PWP FL FW FWP FWA PRFL PRFWA PRFWP INL INWA INWP EYE AG PG INR NR RH RW PNL ANL PROW PROLD PROLV LD LV LHT LL LH DSR1 VR TML

-0.028 -0.011 -0.305 -0.047 0.078

-0.288 0.290 0.048 0.624

-0.093 -0.425 -0.513 0.278 0.286

-0.249 0.576

-0.693 -0.062 0.360

-0.404 0.194

-0.129 0.138

-0.496 -0.032 -0.232 -0.093 0.130

-0.287 -0.023 -0.067 0.805 0.050

-0.073 0.399

-0.432 -0.196 0.308

-0.217 -0.200 0.645 0.176 0.583

-0.318 0.171

-0.645 0.064 0.225

-0.225 0.663

0.280 -0.246 -0.178

0.026 -0.436

0.210 0.043

-0.966 -0.234 -0.014

0.021 -0.054 -0.481

0.231 -0.149

0.359 -0.848 -0.777 -0.069 -0.274

0.122 -0.373

0.237 -0.158 -0.391

0.177 -0.405 -0.287

0.562 -0.046

0.214 -0.077 -0.179 -0.095

0.031 -0.784

0.235 0.248 0.295 0.347

-0.176 -0.292 -0.199 -0.292

0.210 0.191 0.285

-0.138 -0.192

0.044

Axis

Character 1 (55.4%) 2 (26.2%) 3 (18.4%)

0.481 VENTRALS -0.209 SUBCAUDALS -0.240 ILLEFT

0.247 DSR10 -0.372 DSR50 -0.025 DSRPEN

0.246 K 0.137 DB 0.762 LB

-0.181 DBW 0.508 DBL 0.000 LBW 0.246 LBL

-0.410 VBLAT 0.248 VBMED

-0.345 SLBN 0.465 ILBN 0.064 TL

-0.559 HL -0.416 PL -0.126 PW -0.123 PWP

0.301 FL -0.294 FW

0.086 FWP 0.552 FW

-0.061 PRFL 0.159 PRFWA 0.115 PRFWP

-0.156 INL 0.515 INWA

-0.469 INWP -0.016 EYE -0.201 AG -0.285 PG

0.378 INR 0.520 NR

-0.066 RH -0.686 RW -0.371 PNL

0.128 ANL 0.018 PROW

-0.448 PROLD 0.809 PROLV

-0.106 LD 0.220 LV 0.637 LHT 0.564 LL 0.055 LH 0.340 DSR1

VR TML

0.513 0.300

-0.058 0.803 0.140 1.204

-0.168 -2.569 -1.510

0.436 -1.876 -0.653

0.249 0.200 1.711 0.955

-0.758 0.072 0.067

-0.213 0.518

-0.638 0.050 0.069 0.317

-1.281 -0.163 -0.415 -0.025 -0.594

0.511 0.914 0.695 0.542

-0.019 0.384

-0.489 1.732

-0.160 -1.084

0.468 -0.334 -1.066

0.00 -1.437 -1.245

0.688 0.173 0.952

-2.265 1.925

-0.087

0.827 -0.786 -0.376

0.342 -2.793 -1.789

0.697 1.414 1.923

-2.214 3.113 0.200 1.501 1.026

-1.165 0.419

- 1.066 -0.688

0.842 0.155 1.380 0.724

-2.519 0.993 0.974

-1.018 0.591

-0.054 -0.458 -2.318

0.741 0.910 0.208

-2.042 0.316 1.381 0.698 0.960 0.399 1.485

-2.424 -0.005

0.007 0.00 1.324 1.358

-1.826 1.149

-0.902 2.053

-1.681 1.298

0.750 -0.126 -0.015

0.217 0.694 0.598

-0.865 -0.688 -0.884

1.069 -1.723 -0.055 -0.082 -0.358

0.739 0.079

-0.273 1.348

-1.520 0.623

-0.687 -0.429

1.170 -1.368 -0.904

0.449 -0.233 -0.338

0.840 0.879

-0.908 0.282 0.953 0.514

-0.266 0.649 0.385

-0.721 0.578

-0.494 1.902

-0.289 0.223 0.00

-0.587 -0.020 -0.947 -0.898

0.029 -1.275

1.543 -0.786


TABLE 7.-Discriminant function classification matrix for males. The table shows the number of specimens correctly classified into their assumed clades based on geographical location using the characters included in each Case. Letters representing clades are E = Eastern, C = Central, W = Western, B = E. bairdi.

Case i Case 2 Case 3 Case 4

Clade E C W B % correct E C W B % correct E C W B % correct E C W B % correct

E 107 18 3 0 84 97 24 1 0 80 26 0 0 0 100 33 1 0 0 97 C 17 87 12 0 75 14 90 7 0 81 0 33 1 0 97 2 44 1 0 94 W 3 5 76 0 90 2 4 76 0 93 0 0 39 0 100 1 0 40 0 98 B 1 0 0 11 92 0 0 0 12 100 0 0 0 1 100 0 0 0 1 100 Total 128 110 91 11 83 113 118 84 12 84 26 33 40 1 99 36 45 41 1 96

TABLE 8.-Discriminant function classification matrix for females. The table shows the number of specimens correctly classified into their assumed clades based on geographical location using the characters included in each Case. Letters representing clades are E = Eastern, C = Central, W = Western, B = E. bairdi.

Case 1 Case 2 Case 3 Case 4

Clade E C W B % correct E C W B % correct E C W B % correct E C W B % correct

E 59 11 1 0 83 58 9 1 0 85 8 0 0 0 100 10 0 0 0 100 C 14 67 9 0 74 9 73 6 0 91 0 27 0 0 100 2 35 2 0 90 W 1 3 44 0 92 3 1 43 0 91 0 0 26 0 100 0 1 32 0 97 B 0 0 0 8 100 0 0 0 8 100 0 0 0 2 100 0 0 0 2 100 Total 74 81 54 8 82 70 83 50 8 86 8 27 26 2 100 12 36 34 2 94

z

0

0

0

2j.


TABLE 9.-Discriminant function classification matrix for males. The table shows the number of specimens correctly classified into their assumed subspecies using the data included in Case 2.

Subspecies E. bairdi E. o. lind. E. o. obs. E. o. quad. E. o. ross. E. o. spil. E. o. will. E. o. deck. % correct

E. bairdi 10 3 1 1 0 0 0 0 67 E. o. lind. 5 43 12 9 5 2 2 6 41 E. o. obs. 3 14 72 20 8 3 4 0 58 E. o. quad. 0 4 3 16 1 1 1 0 62 E. o. ross. 0 2 2 0 11 1 0 0 69 E. o. spil. 4 0 0 0 3 16 0 2 64 E. o. will. 0 0 0 0 0 0 4 0 100 E. o. deck. 0 0 0 0 0 0 0 4 100 Total 22 66 90 46 28 23 11 12 59

by using the morphological data presented in Appendix II. All subspecies have been defined on one or two color pattern characters that are inconsistent within their putative ranges. The two widest ranging subspecies, Elaphe o. obsoleta and E. o. lindheimeri, are the most difficult to classify morphologically and genetically. The subspecies E. o. obsoleta cannot be defined when using the subjective character: black with little pattern. This general dark pattern has evolved three times in each of the three clades or is a retained ancestral feature in the three clades (Burbrink et al., 2000). Many authors have commented that blotched ratsnakes appear well within the geographic range of supposedly unpatterned E. o. obsoleta (Hurter, 1911; Hudson, 1942; McCauley, 1945; Conant, 1951; Smith, 1961; Barbour, 1971; Minton, 1972; Mount, 1975; Vogt, 1981; Dundee and Rossman, 1989; Oldfield and Moriarty, 1994). Numerous specimens examined during this study that were collected in the range of E. o. obsoleta were clearly patterned like E. o. lindheimeri or E. o. spiloides: KS-Douglas Co.: KU 558, 2450;

WI-Iowa Co.: MPM 8805; NC-Macon Co.: NCSM 14345; IL-Fayette Co.: INHS 12494; OH-Montgomery Co.: LSUMZ 5825, 59265; NE-Cass Co. UNSM 549, 2236). Very dark specimens of E. o. obsoleta in Virginia and North Carolina exhibit the same stripes that are a key character for identifying E. o. quadrivittata (Mitch- ell, 1994; Braswell, 1977) (multple examples of this pattern class can be found in the NCSM collection: e.g., NC-Brunswick Co.: NCSM 2178, 3851, 12467, 15419, 16773). The striped dorsal pattern and yellow ground color of E. o. quadrivittata grade into the black color pattern of E. o. obsoleta in a large area of North Carolina, South Carolina and Georgia (Braswell, 1977). The brown, orange or yellow ground color described for E. o. lindheimeri in Louisiana appears to lighten grad- ually into the gray ground color described for E. o. spiloides in eastern Alabama. This gradation in color pattern makes it difficult to allocate specimens to subspecies from central or western Alabama (numerous examples of these intermediate pattern clas- ses can be found in the AUM collection:

TABLE 10.-Discriminant function classification matrix for females. The table shows the number of specimens correctly classified into their assumed subspecies using the data included in Case 2.

Subspecies E. bairdi E. o. lind. E. o. obs. E. o. quad. E. o. ross. E. o. spil. E. o. will. E. o. deck. % correct

E. bairdi 6 0 0 1 0 0 0 0 86 E. o. lind. 2 45 11 2 0 0 0 1 74 E. o. obs. 0 15 42 8 4 4 0 0 58 E. o. quad. 0 0 0 14 1 1 1 0 82 E. o. ross. 0 0 0 1 8 1 0 0 80 E. o. spil. 0 1 2 0 0 9 0 0 75 E. o. will. 0 1 0 1 0 0 2 0 50 E. o. deck. 0 0 0 0 0 0 0 6 100 Total 8 62 55 27 13 15 3 7 69



(22,17)

FIG. 13.-Map of the United States showing the location of populations used in the specific eastern and central clade DFA, where individual populations are used as operational groups. Values outside of parentheses indicate population number. Values within parentheses indicate the numbers of males and females examined for each population, respectively.

AL-Baldwin Co.: 414, 1030; Lee Co.: AUM 430, 1723, 2047, and 32509). Elaphe obsoleta spiloides west of the Apalachicola River and east of Mobile Bay look like gray E. o. lindheimeri.

Elaphe obsoleta deckerti from the Flor- ida Keys and E. o. williamsi from Levy Co., Florida, can be classified by using DFA (Tables 9, 10). However, both of these subspecies occupy small ranges and it may be possible to classify them morphologically because of local adaptations. Dowling (1951) and Schultz (1996) considered E. o. williamsi to be an intergrade between E. o. spiloides and E. o. quadrivittata (Dowling, 1951; Schultz, 1996). The pattern and range of this form is intermediate between E. o. spiloides and E. o. quadrivittata (Dowling, 1951; Christ- man, 1980). Many E. o. quadrivittata from Alachua Co., FL examined in this study

were also heavily blotched and had stripes like E. o. williamsi. In preservative, these specimens appear identical to the gray E. o. williamsi (see specimens UF 2734, 2762, 14351, 19333, 49264, 49443, and 64983 from Alachua Co., FL). Genetically, E. o. williamsi appears to be related to individuals categorized as E. o. spiloides from Taylor Co., FL and Liberty Co., FL and clearly is a member of the distinct eastern clade (Fig. 2). E. o. williamsi also appears to be morphologically grouped with the eastern clade.

The southern Florida and Florida Keys form, Elaphe o. deckerti, also appears morphologically distinct according to DFA (Tables 9, 10). However, it is very difficult to assign specimens to that subspecies from the color patterns used to define it. Numerous specimens in the Florida Keys and southern Florida appear identical to



TABLE 11.-List of localities for populations included in the specific eastern and central clade DFA as displayed in Fig. 13.

Eastern clade Population 1-Connecticut: Fairfield Co., New Haven Co., New London Co.; New York: Dutchess Co.,

Putnam Co., Ulster Co., Westchester Co. Population 2-Maryland: Frederick Co.; Virginia: Bedford Co., Loudon Co. Population 3-North Carolina: Sampson Co. Population 4-North Carolina: Brunswick Co.; Carteret Co. Population 5-Florida: Duval Co.; Georgia: Camden Co., Cobb Co., Glynn Co., Liberty Co.; North Caroli-

na: Avery Co., Cherokee Co., Wayah Bald Mt: South Carolina: Charleston Co. Population 6-Georgia: Blecldey Co., Columbia Co., Dekalb Co., Emanuel Co., Irwin Co., McIntosh Co.,

Newton Co., Rabun Co., Richmond Co., Screven Co.; North Carolina: Macon Co., Transylvania Co.; South Carolina: Aiken Co., Bamberg Co., Fairfield Co., Lexington Co., Orangeburg Co., Richland Co.

Population 7-Florida: Alachua Co., De Soto Co., Gilchrist Co., Hernando Co., Hillsboro Co., Indian River Co., Marion Co., Martin Co., Orange Co., Palm Beach Co., Pinellas Co., Polk Co., Putnam Co., Semi- nole Co., Sumter Co.

Population 8-Florida: Broward Co., Collier Co., Dade Co. Population 9-Florida: Monroe Co. Population 10-Florida: Citrus Co., Levy Co. Population 11-Florida: Columbia Co., Dixie Co., Gilchrest Co., Leon Co., Suwannee Co., Taylor Co.,

Wakulla Co.; Georgia: Baker Co., Clinch Co., Grady Co., Harris Co., Lowndes Co., Ware Co. Central clade Population 12-Alabama: Baldwin Co., Calhoun Co., Clarke Co., Cleburne Co., Cherokee Co., Coffee Co.,

Dale Co., Elmore Co., Lee Co., Macon Co., Madison Co., Mobile Co., Monroe Co., Pike Co., Randolph Co., Shelby Co., Talladega Co., Washington Co.; Florida: Escambia Co., Holmes Co., Okaloosa Co., San- ta Rosa Co., Walton Co.

Population 13-Louisiana: Ascension Par., East Baton Rouge Par., East Feliciana Par., Iberville Par., Liv- ingston Par., St. Charles Par., St. Tammany Par.; Mississippi: Forrest Co., Hancock Par., Harrison Par., Pearl River Co., Smith Co., Wilkinson Co.

Population 14-Pennsylvania: Allegheny Co. Population 15-Kentucky: Ballard Co., Calloway Co., Carlisle Co., Fulton Co., Graves Co., Hickman Co.,

Marshall Co.; Tennessee: Cumberland Co., Decatur Co., Hardeman Co., Knox Co., Lawrence Co., Montgomery Co., Morgan Co.

Population 16-Indiana: Vermillion Co.; Michigan: Eaton Co., Scioto Co. Population 17-Illinois: Adams Co., Bond Co., Calhoun Co., Clark Co., Clay Co., Cole Co., Effingham Co.,

Fayette Co., Gallatin Co., Green Co., Hamilton Co., Jackson Co., Jasper Co., Jefferson Co., Jersey Co., Johnson Co., Jasper Co., Madison Co., Monroe Co., Montgomery Co., Perry Co., Pope Co., Randolph Co., Richland Co., St. Clair Co., Union Co., Vermillion Co., Washington Co., White Co., Williamson Co.; Indiana: Brown Co.

Population 18-Wisconsin: Crawford Co., Grant Co., Iowa Co., LaCrosse Co., Richland Co., Sauk Co.

E. o. quadrivittata or E. o. rossalleni. The following specimens on the Florida Keys fail to have the prominent blotches thought to distinguish E. o. deckerti from the faintly patterned E. o rossalleni: FL: Monroe Co.: LSUMZ 34312, 28870; MCZ 12519. In addition the red tongue that distinguished E. o. rossalleni from the black- tongued E. o. deckerti also fails to be a reliable character. The following specimens within the range of E. o. rossalleni near the Everglades in Dade Co., FL have either black or mottled red and black tongues: UF 113924, 113927; CM 51024. The traditional characters that distinguish E. o. quadrivittata, E. o. rossalleni, and E.

o. deckerti from one another often fail. Genetically, E. o. deckerti forms a clade with the central Florida E. o. quadrivittata. These striped forms are genetically part of the eastern clade and can be classified morphologically within that clade (Fig. 2).

From the univariate and multivariate analyses, it is apparent that head scale shapes and scale counts vary greatly between clades (the specific differences are described below). It is also evident that detailed color pattern measurements aid in defining the boundaries between clades These color pattern measurements should not be confused with the original vague color patterns used to describe the sub-


26HREOOIA MNGAH N.1

Population o 1 x2

4 i +3 A/4

3 5 ~i - v5

2 - Central / - \ - 6 Clade > -7 Cl

0 o- *V^^^^V10

00DF ~ 12

-2- o > <> 14

*.~ _ \ U/'0 /15 -3 El 0 16

4 I I \ 17 -10 -5 0 5 18

Eastern Clade

DF1 FIG. 14.-Bi-plots of the first two discriminant function scores produced from the specific eastern and

central clade population DFA for males. Convex hulls around points indicate the boundaries of eastern and

central clade members.

species. When examined in detail, it is clear that color patterns like DB, LB, DBW1, DBL1, LBW1, and LBL1 vary substantially across the geographical boundaries that were once thought to de- limit subspecies with homogeneous color patterns (Tables 1, 2). Superficially, the color pattern of E. o. lindheimeri was considered to be the same on both sides of the Mississippi River. In detail, color patterns are clearly different in dorsal blotch number and shape. A similar situation arises for E. o. spiloides at the Apalachicola River. By using the traditional color characters, gray ground color and dark blotches, it might be assumed that this subspecies has the same color pattern on both sides of the Apalachicola River. However, patterns present on specimens from east

and west of the river different in shape and number (Tables 1, 2).

Based on the findings presented here, it seems that subspecies described from only a few color characters are unlikely to reflect the evolutionary history of the taxa in question, especially in cases where individual subspecies are thought to cross known geographic barriers. Examples from North American snakes may include Crotalus horridus, Agkistrodon contortrix, Lampro- peltis getula, L. triangulum, and Coluber constrictor. This study suggests that the taxonomy of a number of polymorphic snakes in the United States may require revaluation. In the last decade several studies have demonstrated that the evolutionary history of reptile species com- plexes is often much different from the

[No. 15 HERPETOLOGICAL MONOGRAPHS 36

201 HEPEOOGCL OOGAHS3

Population

ol 1 6 I I I I I I I x2

6 , , , i , a , , i v + 3 5 _ Eastern

_

A 4 Clade / 5

4 - \ / - - Central - <6

3 _Y/- - \ Clade

< 14

*17

Q - 2 o 1912 3 4 5

~~DF ~1~ ~10

FIG. 15. Bi-plots of the frst two discriminant lunction scores produced from the specific eastern and

central ade memers 11

-13

f:17

-5 -4 -3 -2 -1 0 1 2 3 4 5

DF 1 FIG. 15.-Bi-plots of the first two discriminant function scores produced from the specific eastern and

central clade population DFA for females. Convex hulls around points indicate the boundaries of eastern and central clade members.

traditionally recognized subspecies (Za- mudia et al., 1997; Rodriguez-Robles, 1999, 2000).

Subspecies may "be a handle of conve- nience for the clerical work of the museum curator" (Mayr, 1982), represent arbitrary sections of a cline (Wilson and Brown, 1953; Mayr, 1982; Cracraft, 1983; Frost and Hillis, 1990), be considered incipient species (Darwin, 1859; Mayr, 1942) , or are masquerading as true species (Frost et al., 1992; Burbrink et al., 2000). Unless subspecies are found to be true species, then they have no real taxonomic meaning with respect to distinct evolutionary lineages. In the case of Elaphe obsoleta, all subspecies, other than the previously elevated E. bair-

di, tend to represent arbitrary pattern clas- ses or sections of an ambiguous cline. Mo- lecular data (Burbrink et al., 2000) strongly suggest that none of the currently recognized subspecies represent distinct evolutionary lineages. In agreement with these data, it has been shown that most subspecies are also difficult to classify morphologically using the data set presented here. Moreover, the traditional characters used to describe these subspecies generally fail to adequately diagnose them. The taxonomic validity of the subspecies of E. obsoleta throughout the past half-century have been preserved under a variant of the inertial species concept (Good, 1994): where untested subspecies or species are

37 2001 ] HERPETOLOGICAL MONOGRAPHS


TABLE 12.-Mean and standard deviation (in parentheses) of mensural ratio measurements for males.

Character ratio

TL/SV HL/SV PL/HL PW/HL PWP/HL FL/HL FW/HL FWP/HL FWA/HL PRFL/IHL PRFWA/HL PRFWP/HL INL/HL INWA/HL INWP/HL EYE/HL AG/HL PG/HL INR/HL NR/HL RH/HL RW/HL PNL/HL ANL/HL PROW/HL PROLD/HL PROLV/HL LD/HL LV/HL LHT/HL LL/HL LH/HL DRS1/SV VR/SV

E. alleghaniensis (Eastern clade)

0.231 (0.019) 0.024 (0.003) 0.216 (0.020) 0.209 (0.012) 0.088 (0.013) 0.225 (0.014) 0.137 (0.010) 0.123 (0.011) 0.190 (0.0013) 0.158 (0.013) 0.151 (0.012) 0.114 (0.012) 0.071 (0.011) 0.120 (0.011) 0.105 (0.011) 0.106 (0.014) 0.211 (0.021) 0.248 (0.025) 0.115 (0.012) 0.080 (0.008) 0.152 (0.013) 0.201 (0.016) 0.060 (0.009) 0.064 (0.008) 0.127 (0.012) 0.084 (0.009) 0.059 (0.008) 0.056 (0.008) 0.085 (0.010) 0.051 (0.007) 0.771 (0.030) 0.129 (0.013) 0.006 (0.000) 0.005 (0.000)

E. spiloides (Central clade)

0.214 (0.016) 0.034 (0.003) 0.220 (0.023) 0.214 (0.013) 0.087 (0.013) 0.227 (0.016) 0.142 (0.013) 0.128 (0.014) 0.189 (0.014) 0.160 (0.017) 0.160 (0.013) 0.122 (0.014) 0.068 (0.013) 0.126 (0.011) 0.109 (0.014) 0.149 (0.015) 0.256 (0.021) 0.244 (0.027) 0.121 (0.003) 0.082 (0.009) 0.166 (0.016) 0.211 (0.017) 0.063 (0.010) 0.068 (0.010) 0.131 (0.011) 0.083 (0.010) 0.058 (0.011) 0.055 (0.009) 0.086 (0.010) 0.054 (0.010) 0.775 (0.032) 0.132 (0.014) 0.006 (0.000) 0.005 (0.000)

E. obsoleta (Western clade)

0.218 (0.022) 0.037 (0.003) 0.227 (0.019) 0.211 (0.014) 0.082 (0.013) 0.220 (0.016) 0.139 (0.010) 0.125 (0.014) 0.192 (0.014) 0.162 (0.010) 0.154 (0.010) 0.121 (0.010) 0.062 (0.015) 0.121 (0.010) 0.109 (0.011) 0.143 (0.011) 0.248 (0.021) 0.238 (0.028) 0.116 (0.014) 0.079 (0.008) 0.162 (0.013) 0.201 (0.014) 0.056 (0.008) 0.068 (0.008) 0.124 (0.011) 0.075 (0.008) 0.055 (0.007) 0.060 (0.010) 0.086 (0.010) 0.052 (0.007) 0.711 (0.027) 0.121 (0.013) 0.006 (0.001) 0.005 (0.000)

E. bairdi

0.250 (0.015) 0.034 (0.002) 0.231 (0.016) 0.196 (0.009) 0.079 (0.028) 0.243 (0.021) 0.136 (0.008) 0.123 (0.008) 0.188 (0.013) 0.155 (0.009) 0.136 (0.018) 0.106 (0.010) 0.079 (0.010) 0.110 (0.011) 0.093 (0.010) 0.149 (0.012) 0.273 (0.021) 0.222 (0.035) 0.092 (0.013) 0.085 (0.007) 0.139 (0.018) 0.185 (0.019) 0.062 (0.008) 0.064 (0.006) 0.064 (0.014) 0.126 (0.012) 0.090 (0.006) 0.063 (0.010) 0.091 (0.009) 0.048 (0.006) 0.770 (0.019) 0.109 (0.006) 0.005 (0.000) 0.005 (0.000)

recognized as taxonomic entities, thus re- sulting in the perpetuation of names based only on historical precedence for those names and not scientific rigor. It is rec- ommended that the subspecies of E. obsoleta no longer be recognized.

The four molecular clades appear to represent four independent lineages, and thus meet the criteria for distinct evolutionary species, each separated by geographical features known to represent barriers to gene flow in other taxa as well (Blair, 1958; Blair, 1965; Wiley and May- den, 1985; Mayden, 1988; Walker et al., 1998). Moreover, the overall morphological evidence reflects the separate evolutionary trends discovered in the sequences of the two mtDNA genes. However, separation between northern members of the

eastern clade and northern members of the central clade is less significant and appear to overlap morphologically (Figs. 14 and 15). Although the convex hulls may be influenced by outliers, this situation is worth investigating in detail. It is possible that individuals from the eastern and central clades are hybridizing due to leaks in gene flow across the Appalachian Moun- tains. Therefore, the mitochondrial genes may be describing a pattern that occurred in the near past, but is unable to account for modern hybridization events. It is also possible that northern individuals in the eastern clade are converging on a standard northern morphology shared by the central clade or that northern members of the eastern clade have failed to diverge from a common ancestral morphotype shared


201 HEPEOLGIA MNORAHS3

TABLE 13.-Mean and standard deviation (in parentheses) of mensural ratio measurements for females.

Character ratio

TL/SV HL/SV PL/HL PW/HL PWP/HL FL/HL FW/HL FWP/HL FWA/HL PRFL/HL PRFWA/HL PRFWP/HL INL/HL INWA/HL INWP/HL EYE/HL AG/HL PG/HL INR/HL NR/HL RH/HL RW/HL PNL/HL ANL/HL PROW/HL PROLD/HL PROLV/HL LD/HL LV/HL LHT/HL LL/HL LH/HL DRS1/SV VR/SV

E. alleghaniensis (Eastern clade)

0.217 (0.025) 0.036 (0.002) 0.209 (0.022) 0.208 (0.012) 0.089 (0.013) 0.223 (0.016) 0.135 (0.012) 0.119 (0.013) 0.190 (0.014) 0.157 (0.012) 0.152 (0.012) 0.114 (0.010) 0.069 (0.012) 0.119 (0.010) 0.106 (0.011) 0.141 (0.013) 0.253 (0.018) 0.244 (0.026) 0.111 (0.013) 0.083 (0.010) 0.152 (0.014) 0.200 (0.016) 0.057 (0.007) 0.063 (0.008) 0.126 (0.010) 0.084 (0.008) 0.058 (0.007) 0.053 (0.008) 0.084 (0.009) 0.048 (0.007) 0.763 (0.028) 0.130 (0.016) 0.005 (0.000) 0.005 (0.000)

E. spiloides (Central clade)

0.197 (0.020) 0.035 (0.003) 0.217 (0.020) 0.218 (0.014) 0.089 (0.014) 0.231 (0.019) 0.142 (0.013) 0.128 (0.016) 0.195 (0.014) 0.164 (0.013) 0.162 (0.014) 0.124 (0.015) 0.067 (0.013) 0.126 (0.014) 0.113 (0.015) 0.150 (0.016) 0.257 (0.023) 0.247 (0.028) 0.120 (0.016) 0.085 (0.011) 0.169 (0.015) 0.209 (0.016) 0.060 (0.009) 0.069 (0.009) 0.132 (0.013) 0.087 (0.011) 0.059 (0.008) 0.053 (0.009) 0.086 (0.012) 0.053 (0.007) 0.782 (0.038) 0.132 (0.015) 0.006 (0.001) 0.005 (0.000)

E. obsoleta (Western clade)

0.204 (0.015) 0.038 (0.003) 0.216 (0.020) 0.209 (0.014) 0.080 (0.012) 0.222 (0.015) 0.140 (0.013) 0.122 (0.015) 0.194 (0.017) 0.163 (0.011) 0.153 (0.008) 0.120 (0.012) 0.061 (0.009) 0.122 (0.010) 0.109 (0.011) 0.140 (0.011) 0.246 (0.018) 0.234 (0.029) 0.114 (0.012) 0.081 (0.011) 0.161 (0.011) 0.196 (0.013) 0.054 (0.007) 0.065 (0.008) 0.126 (0.012) 0.077 (0.010) 0.056 (0.007) 0.057 (0.009) 0.085 (0.008) 0.052 (0.005) 0.770 (0.026) 0.199 (0.011) 0.006 (0.000) 0.005 (0.000)

E. bairdi

0.229 (0.010) 0.034 (0.002) 0.233 (0.020) 0.194 (0.013) 0.075 (0.009) 0.246 (0.017) 0.136 (0.010) 0.118 (0.015) 0.188 (0.018) 0.156 (0.007) 0.142 (0.009) 0.115 (0.012) 0.081 (0.011) 0.104 (0.025) 0.092 (0.006) 0.152 (0.012) 0.269 (0.022) 0.209 (0.059) 0.087 (0.018) 0.090 (0.008) 0.141 (0.018) 0.191 (0.016) 0.059 (0.007) 0.064 (0.008) 0.124 (0.022) 0.093 (0.010) 0.064 (0.008) 0.065 (0.005) 0.100 (0.007) 0.051 (0.005) 0.771 (0.021) 0.106 (0.009) 0.005 (0.000) 0.005 (0.000)

by the central clade. The extent of hybridization and the details of each boundary between all clades may better be examined using quickly evolving nuclear markers such as microsatellites. An exhaustive study examining the influence of environment and genetic history on morphology similar to those performed by Thorpe et al. (1996) and Malhotra and Thorpe (2000) may also help determine the nature and dimensions of clade boundaries and how much of the morphology actually accounts for evolutionary history.

Although the eastern and central clade may be found to currently form a single lineage, the evidence presented here demonstrates that all four clades represent in- dependently evolving units with respect to the evolutionary species criteria in light of

the general lineage concept (deQueiroz, 1998). Because the taxonomy of a complex should reflect its evolutionary history (Frost and Hillis, 1992), I propose the following species names for the four groups: eastern clade = Elaphe alleghaniensis; central clade - E. spiloides; western clade = E. obsoleta; E. bairdi = E. bairdi.

Although the range of values for many characters overlap among Elpahe alleghaniensis, E. spiloides, and E. obsoleta, descriptions of morphological trends will be discussed below in the accounts for each species. Beacuse the differences between E. alleghaniensis, E. spiloides, and E. obsoleta are subtle, particular attention will be placed on their various morphological differences. Elaphe bairdi is distinct morphologically relative to the other three

2001oo HERPETOLOGICAL MONOGRAPHS 39


Elaph,e baird. E l:lpahe obsoiera

FIG. 16.-Putative distribution for Elaphe alleghaniensis, E. spilopides, E. obsoleta and E. bairdi. Within the range of E. alleghaniensis a potential area of taxonomic uncertainty is indicated with a bold outline.

species, and will be discussed only in terms of its degree of differentiation from the other three species as a group.

Elaphe alleghaniensis (Holbrook) Coluber alleghaniensis Holbrook, 1836:

111, pl. 20. Type locality: "summit of the Blue Ridge in Virginia and Highlands of the Hudson." (Holotype: ANSP 16792).

Coluber quadrivittatus Holbrook, 1836: 113-14, pl. 21.

Scotophis confinis Baird and Girard, 1853: 77.

Coluber obsoletus lemniscatus Cope, 1888: 386 (Part).

Elaphe quadrivittata deckerti Brady, 1932: 5.

Elaphe williamsi Barbour and Carr, 1940: 340.

Elaphe quadrivittata parallela Barbour and Engels, 1942: 103.

Elaphe obsoleta rossalleni Neill, 1949: 1.

Nomenclature.-The two oldest names for the type specimens found within the eastern clade are Coluber alleghaniensis and C. quadrivittatus (Holbrook, 1836). Elaphe allegheniensis is applied to the eastern clade because C. alleghaniensis appears in the original edition of North American Herpetology (Holbrook, 1836) two pages earlier than does C. quadrivit-

tatus. This decision has an added benefit in that E. quadrivittata is typically associated with the yellow and black-striped form and would likely be incorrectly applied only to those specimens by the lay- person. The name E. alleghaniensis has not been previously applied to nonmono- phyletic subsets of the E. obsoleta complex and is therefore less likely to create taxonomic confusion.

Standard English name. -Eastern Rat- snake.

Distribution.-This species occurs east of the Apalachicola River in Florida, east of the Chattahoochee River in Georgia, east of the Appalachian Mountains, north to southeastern New York and western Vermont and south to the Florida Keys. The distribution of this species in the northern areas, particularly north of Flor- ida, may be somewhat questionable with regard to hybridization with members of Elaphe spiloides. Therefore, northern parts of the range may be considered as areas of potential taxonomic uncertainty (Fig. 16).

Diagnosis.-Elaphe alleghaniensis is a large colubrid with a SVL averaging 1092 mm for males and 1020 mm for females (Tables 1, 2). The tail length averages 242 mm for males and 213 mm for females.


Pouential Arca of T-xonomm .ncertalmnt,


The large elongated head of this species is distinct from the neck. This semi-arboreal snake has a laterally compressed body slightly higher than wide. Both sexes of this species usually have eight supralabials, 11 or 12 infralabials, one preocular, two postoculars, and eight or nine total temporal scales (Tables 1, 2). Keels begin at midbody on scale rows three or four for both sexes. Males and females usually have 25 or 27 scale rows at the level of the tenth ventral scale, 25 or 27 scale rows at midbody, and 19 or 21 scale rows at the level of the penultimate ventral scale. Sexual dimorphism exists for many characters, with males having the higher value for most characters except ventral number and DBW1 (see Results).

Individuals of Elaphe alleghaniensis tend to have a higher number of subcaudals (males, x = 89.147; females, x = 82.071) than E.spiloides (males, x = 82.175; females, x = 76.228) and E. obsoleta (males, x = 82.769; females, x =

77.617). Along with this character, the ratio of TL/SV is higher in E. alleghaniensis than E. spiloides or E. obsoleta (Tables 12, 13). When dorsal blotches are present, E. alleghaniensis has a higher number (males, x = 34.993; females, =- 35.035) than E. spiloides (males, x = 30.523; females, x = 29.763) and E. obsoleta (males, x = 31.353; females, x = 30.439). Ratsnakes with smaller dorsal blotches have high numbers of blotches. The DBW1 and DBL1 in E. alleghaniensis are smaller than E. spiloides and E. obsoleta. Although not as significant, E. alleghaniensis has a higher number of shorter lateral blotches than E. spiloides and E. obsoleta.

The variation in head scale characters is noticeable between these three species and is better viewed as a ratio with head length as the common denominator (Ta- bles 12, 13). Elaphe alleghaniensis differs from E. spiloides and E. obsoleta in having a much shorter rostral height (RH), a narrower head, and longer muzzle. The narrower head is reflected in the smaller size of the following dorsal head scales in males: PW/HL, FW/HL, FWP/HL, PRFWA/HL, PRFWP/HL, INWA/HL, INWP/HL, and INR/HL. These charac-

ters tend to be smaller in females as well, but with the addition of FWA/HL. The following length variables are marginally shorter in both sexes of E. alleghaniensis: PL/HL, PRFL/HL. RW (as determined by the ratio: RW/HL) is narrower and the LL (as determined by the ratio: LL/HL) is shorter than in the other members of this complex. Differences between E. alleghaniensis and E. bairdi are discussed in the E. bairdi species account.

Color variation.-Numerous color patterns can be found in Elaphe alleghaniensis. This species may be black with no pattern, yellow with black or brown stripes, orange with little evidence of any pattern, gray with brown or black blotches or have combinations of all of these color patterns. The darkest adult specimens are found in eastern New York, western New Hamp- shire, Connecticut, New Jersey, Maryland, eastern Virginia, North and South Carolina (excluding the eastern coasts), and northern and central Georgia. These specimens usually have black or dark brown ground colors. The dorsal pattern may be visible as blotches on the dark brown ground col- or, or as white flecks that once composed the border of faded blotches on a black ground color. Other specimens in the northern part of the range are completely black with no trace of color. The patterned specimens often have a series of medial dorsal blotches and alternating lateral blotches on the side of the body, with most visible blotches occurring at midbody. The dark northern specimens usually have two rows of ventral blotches that occupy two or three scales and are visible anteriorly, but connect medially and produce an almost black venter before midbody. Lateral blotches that occupy two or three scales are also present on the anterior half of the venter. By midbody, these lateral blotches are usually not visible due to the dark venter. The ventral surface of the tail is usually black, but some specimens retain a light medial stripe that is often present in juveniles. These dark individuals usually have a black or brown head with white supralabials and infralabials. Prominent dark bars are often found on the first six supralabials and the first eleven, twelve, or



thirteen infralabials. The ventral surface of the head is usually white.

Specimens in southeastern Virginia often show the presence of dorsal and lateral black stripes on a dusky dark gray or brown dorsal surface (Mitchell, 1994). This pattern appears to be intermediate between the dark northern specimens and the dark-striped, olive, tan or yellow Ela- phe alleghaniensis of coastal North Caro- lina, South Carolina, Georgia and coastal and central Florida. The intermediate col- or patterns from individuals from North Carolina are described in detail by Bra- swell (1977). They appear to have a dusky gray or olive ground color with two dorsal dark brown or black stripes and two lateral brown or black stripes on either side of the body. The dorsal stripes run from the neck to tail tip, whereas the lateral stripes begin at the neck and end at the level of the cloaca. In addition, dorsal blotches are present in many specimens, but the lateral blotches are often obscured by the dark lateral stripe. They tend to have diffuse or peppery medial ventral blotches that connect and form two rows from midbody to the tail. Anteriorly, these blotches occupy two or three scales. Lateral ventral blotches also occupy two or three scales and are obscured by the dark dorsum by midbody. A prominent light medial line may be found on the ventral surface of the tail. The head of each specimen appears dark olive and has dark labial bars that are similar to those of black specimens in the northern part of their range.

The dusky, striped color pattern occurring in specimens from central North Car- olina, South Carolina and Georgia even- tually grades into a lighter tan or yellow form known from southeastern North Car- olina, coastal South Carolina, coastal Geor- gia, and northwestern and central Florida. Dusky gray or brown dorsal blotches are often visible in these specimens. The ventral surface is usually much lighter on the anterior third of the body. Light peppering or dark cresents formed on the posterior margin of each scale may be evident from midbody to the tail. Dark ventral blotches may also be present in some specimens. The lateral ventral blotches usually occupy

two to three scales and begin before midbody. By midbody, these lateral blotches usually join to form a stripe that runs to the tip of the tail, but may not be present in all specimens. The head and labial barring is often very light and may be absent in some individuals.

In southern Florida, the dorsal ground color may be orange or rust. Specimens may have completely immaculate, peppered, or blotched venters. Dorsal and lateral blotches may be present. Striping may be absent or show no color pattern. Spec- imens from the Florida Keys may be strongly blotched and appear similar to the northern blotched black ratsnakes.

In Levy Co. and Northern Citrus Co., Florida, Elaphe alleghaniensis have a gray dorsal ground color with black or brown blotches and stripes. This pattern grades into the lighter yellow and striped snakes of central and northwestern Florida. They usually have a blotched or peppered venter. Lateral ventral blotches are often clearly visible from the neck to the cloaca and the tail may retain the light medial line displayed in the juveniles. The gray head may be heavily peppered with small black flecks. The anterior labial scales are often marked with large black bars.

To the west, from Taylor Co., to the Ap- alachicola River and Chatahoochee River through central Georgia, the stripes are absent, but the gray ground color, dark blotches, peppered head, blotched or peppered venter, and barred labials remain. These specimens appear similar to the striped specimens from Levy Co., Florida. This gray and dark blotched form grades into the black form of central and northern Georgia. A postocular stripe that runs through the postocular scales, the first row of temporal scales, and the seventh or eighth supralabial scale is present in most specimens. In addition, a dark stripe may be present at the margin of the prefrontal and frontal scales.

The numerous adult color patterns found in Elaphe alleghaniensis grade into one another over large areas. Further- more, color patterns thought to be char- acteristic of particular regions often occur in regions thought to be inhabited exclu-



sively by ratsnakes with completely different color patterns, indicating that the color patterns are not representative of natural groups. Given the geographically mosaic nature of color patterns in E. alleghaniensis, the exact boundary of any color pattern could not be determined with accuracy.

Elaphe spiloides (Dumeril, Bibron, and Dumeril)

Elaphis spiloides Dumeril, Bibron, and Dumeril, 1854: 269. Type locality: "La Nouvelle-Orleans" = New Orleans, Louisiana. (Holotype: MNHN 827).

Coluber obsoletus lemniscatus Cope, 1888: 386. (Part).

Nomenclature.-The oldest type specimen found within the central clade is Ela- phis spiloides. Blaney (1971) indicated that the holotype could not have originated from New Orleans, Louisiana, because the subspecific color pattern exhibited by the former E. o. spiloides does not exist in southeastern Louisiana. The holotype was measured for all characters listed in Ap- pendix II and statistically analyzed. DFA clearly places the holotype within the central clade (E. spiloides). Therefore, the holotype must have originated within the range of the central clade.

Standard English name.-Central Rat- snake

Distribution.-This species occurs west of the Apalachicola River and the Appa- lachian Mountains and east of the Missis- sippi River. It is found south from Loui- siana along the Gulf Coast of the US to Florida, and north in western New York, east through southern Ontario, Canada, southern Michigan, northeastern Indiana, central Illinois and southwestern Wiscon- sin (Fig. 16).

Diagnosis.-Elaphe spiloides is a large colubrid with a SVL averaging 1097 mm for males and 1007 mm for females (Ta- bles 1, 2). The tail length averages 229 mm for males and 195 mm for females. Like E. alleghaniensis, this species has a large elongated head distinct from the neck. This semi-arboreal species also has a laterally compressed body that is slightly higher than wide. Males have higher val-

ues than females for most measurements and scale counts (see Results). However, females have higher infralabial and temporal counts. Both sexes usually have eight supralabials, 11 to 14 infralabials, one preocular, two postoculars, and eight to ten temporal scales (Tables 1, 2). At midbody, keels begin on scale row three or four for both sexes. Males and females usually have 25 or 27 scale rows at the level of the tenth ventral scale, 25 or 27 scale rows at midbody, and 19 or 21 scale rows at the level of the penultimate ventral scale.

Elaphe spiloides differs from E. alleghaniensis by having fewer subcaudals, fewer dorsal blotches, and a larger DBW, DBL, LBW, and LBL (Tables 1, 2). This species generally has a smaller DBW and DBL than E. obsoleta. Although there is considerable overlap in the ranges of mensural characters, E. spiloides tends to have a broader head than E. alleghaniensis and E. obsoleta as reflected in the head scale measurements. Male and female E. spiloides have larger values than E. alleghaniensis for the following ratios: PL/HL, PW/ HL, FW/HL, FWP/HL, PRFWA/HL, PRFWP/HL, INWA/HL, INWP/HL, EYE/HL, AG/HL, INR/HL, RH/HL, RW/ HL, ANL/HL, PROW/HL, LHT/LV, LL/ HL (Table 12). Females of E. spiloides also have larger values than E. alleghaniensis for the following ratios: FL/HL, FWA/HL, PRFL/HL, NR/HL, PG/HL, PNL/HL (Table 13). Males and females E. spiloides have larger ratio measurements than E. obsoleta for the following characters: PW/HL, PWP/HL, FL/HL, FW/HL, FWP/HL, PRFWA/HL, INL/HL, INWA/ HL, EYE/HL, AG/HL, PG/HL, INR/HL, NR/HL, RH/HL, RW/HL, PNL/HL, PROW/HL, PROLD/HL, PROLV/HL, LL/HL, and LH/HL (Table 13). Females of E. spiloides tend to have higher values than E. obsoleta for the following ratios: PRFWP/HL, INWP/HL, and ANL/HL (Table 13).

Color variation.-Elaphe spiloides does vary greatly in the degree to which specimens are blotched or completely black. Unlike E. alleghaniensis, this species does not have populations characterized by a



striped color pattern. Most dark specimens are found in the northern part of the range: northeastern Alabama to western Pennsylvania and western New York across central and northern Ohio, Indiana, Mich- igan, Illinois, and Wisconsin. It should be stressed that this is only a trend in color pattern and that clearly blotched specimens are found well within those states. The black specimens usually retain some blotching well into adulthood, and traces of red, orange or yellow may be found on the skin between dorsal scales. The head is usually dark olive, brown, or black with dark supralabial bars. Medial blotches, dark flecking, or peppering often occur before midbody on the venter. These markings may be visible to the tail or obscured by a heavy wash of black pigment that often occurs over the posterior half of the body. Lateral blotches on the ventral surface occupy two or three scales and are usually obscured by the dark ventral pigmentation beginning before midbody. Many specimens have a light medial line on the tail. The amount of ventral blotching and black pigmentation is variable in dark northern specimens.

Distinctly blotched specimens are found throughout the ranged of this species, but predominate in Louisiana, Mississippi, Al- abama, Florida, western Kentucky, western Tennessee, southern Illinois and southern Indiana. Near the Mississippi River, specimens often have a tan or brown ground color. This tends to become lighter tan or yellow in eastern Louisiana, yellow in Mississippi and western Ala- bama, and gray in eastern Alabama and western Florida. However, individuals with a dark brown ground color do occur in eastern Louisiana and Mississippi. The ground color is usually darker in the northern part of their range. The blotches are usually black, dark brown, or dark olive. The skin between the dorsal scales may be bright orange, red, yellow, brown, or gray. The head is usually gray, olive, brown or black. Specimens in eastern Alabama and western Florida usually have a gray head that is very heavily peppered or flecked with dark pigment. Blotched specimens may also retain a postocular stripe that

runs through the postocular scales, the first row of temporal scales, and the seventh or eighth supralabial scale. In addition, a dark stripe may be noticeable at the margin of the prefrontal and frontal scales. Supralabial barring is also common in these blotched specimens. Light, diffuse, peppery or solid black blotches are very common on the ventral surface. The blotches usually occur before the 30th ventral scale and are often visible to the cloaca. Occasionally, the ventral surface is heavily mottled posterior to midbody ob- scuring the blotches. Blotches in some individuals appear as dark crescents located at the posterior margin of each ventral scale. Most specimens have a light medial line on the ventral surface of the tail.

Patterned and unpatterned dark specimens occur randomly throughout the northern range of this species. Blotched individuals occur as far north as Wisconsin, and very black individuals occur as far south as southern Louisiana. Many populations considered to be black have distinctly blotched patterns on a dark brown dorsum.

Elaphe obsoleta (Say) Coluber obsoletus Say (in James), 1823:

140. Type Locality: "On the Missouri River from the Vicinity Isle au Vache to Council Bluff." This locality extends from near Leavenworth, Kansas to Council Bluffs, Iowa. (Holotype: Pres- ence is unknown.)

Scotophis laetus Baird and Girard, 1853: 1977.

Scotophis lindheimeri Baird and Girard, 1853: 74.

Nomenclature. -Although missing, the oldest type specimen from the western clade is Coluber obsoletus, collected some- where between Cow Island (near Leav- enworth), Kansas and Council Bluffs, Iowa. This area is clearly within the range of the western clade and the name Elaphe obsoleta should be applied to all members of that clade.

Standard English name.-Western Ratsnake

Distribution.-Occurs west of the Mis-



sissippi River from southern Louisiana along the Gulf Coast to southern Texas, west to central Texas on the Edward's Pla- teau, and through Oklahoma, central and eastern Kansas, southeastern Nebraska, southeastern Iowa, and extreme southeastern Minnesota (Fig. 16).

Diagnosis.-Elaphe obsoleta is similar to E. alleghaniensis and E. spiloides. The average adult SVL is 1078 mm for males and 1002 mm for females (Tables 1, 2). The tail length averages 225 mm for males and 196 mm for females. The head is large and elongated and is well separated from the neck. This semi-arboreal snake also has a laterally compressed body that is slightly higher than wide. Males tend to have a higher value for most characters (see Re- sults). However, females have a higher ventral scale count and a higher number of scale rows at the level of the penultimate ventral scale (Tables 1, 2). Both sexes usually have eight supralabials, 11 to 14 infralabials, one preocular, two postoculars, and ten or 11 temporal scales (Tables 1, 2). Keels begin at midbody on scale row three or four for both sexes. Males and females have 25 or 27 scale rows at the level of the tenth ventral scale, 25 or 27 scale rows at midbody, and 19 or 21 scale rows at the level of the penultimate ventral scale.

Individuals of Elaphe obsoleta tend to have fewer subcaudals, fewer dorsal blotches and fewer lateral blotches than E. alleghaniensis (Tables 1, 2). Individuals of Elaphe obsoleta tend to have a larger DBW1, DBL1, and LBW1 than E. alleghaniensis and E. spiloides. Compared to E. alleghaniensis, male E. obsoleta have larger ratio measurements for the following characters: HL/SV, PL/HL, PRFL/HL, EYE/HL, AG/HL, RH/HL, ANL/HL, LD/ HL (Table 12). Most of these ratios are larger in females except for EYE/HL and AG/HL, which are considerably smaller (Table 13). FW/HL, FWA/HL, and PRFWP/HL are larger in female E. obsoleta than in female E. alleghaniensis. For both sexes, most other characters tend to be of similar size or smaller than in E. alleghaniensis (see E. alleghaniensis species description). Most mensural ratio mea-

surements are smaller in male E. obsoleta than E. spiloides except HL/SV, PL/HL, FWA/HL, and LD/HL. Only HL/SV and LD/SV are larger in female E. obsoleta than in female E. spiloides. The characters that are larger in E. spiloides than in E. obsoleta are discussed in the E. spiloides account.

Color variation.-The color patterns in Elaphe obsoleta are very similar to those found in E. spiloides. Black E. obsoleta, with little pattern, are common in the following northern parts of their distribution: northwestern Louisiana, central and western Arkansas, central and western Oklahoma, Kansas, Nebraska, Missouri, Iowa and Minnesota. However, heavily blotched specimens with black blotches on a dark brown ground color may also be found in the northern regions. Specimens throughout the range of E. obsoleta have red, yellow, or orange colored skin between the dorsal scales. Very light flecks that border the blotches in juveniles can often be seen in the dark black adult specimens. Lateral ventral blotches usually occupy two or three scales and are obscured by the dark ventral pigment just anterior to the midbody. Medial ventral markings may be in the form of two connected rows of blotches, random dark peppering, or dark crescents along the margin of each ventral scale. The ventral surface often be- comes completely black by midbody. Oc- casionally, specimens within the range of these dark specimens have very light unpatterned venters. A light medial line on the ventral surface of the tail is present in many individuals. The head is usually very black without any postocular striping. Bars may be present or absent on the labial scales.

Blotched individuals occur in central and southern Louisiana, Texas, near the Mississippi River in Tennessee, Arkansas, Missouri, Iowa, and Minnesota, most of Oklahoma and southern Kansas. These blotched individuals often have a tan, brown, or dark brown ground color and black or olive blotches. The blotches are often ornamented with minute white flecks. The interstitial skin color may be orange, red, yellow, or gray. Many speci-



mens have blotched medial ventral surfac- es that continue uninterrupted to the tail. Often, individuals in western Louisiana, Texas, and Oklahoma have the medial crescent pattern on the venter. A light medial line is also common in many of the patterned E. obsoleta. A postocular stripe and a bar along the posterior margin of the prefrontal are visible in some specimens. Prominent dark labial barring is present in most specimens, but labial barring may be faint or absent in some individuals.

Patterned and unpatterned black specimens occur sporadically throughout the northern range of this species. Like Elaphe spiloides, it would be very difficult to classify all members of this highly variable species as either purely black or completely patterned.

Elaphe bairdi (Yarrow)

Coluber bairdi Yarrow (in Cope), 1880: 492. Type Locality: Fort Davis, Apache Mountains, Jeff Davis Co.: Texas. (Ho- lotype: USNM 10403).

Nomenclature.-This taxon was elevated to species status by Olson (1977), and no confusion exists with respect to the name associated with the holotype.

Common name.-Baird's Ratsnake. Distribution. -Southwestern Texas

from the Edward's Plateau to the northeastern buttresses of the Sierra Madre Oriental to southern Nuevo Leon, Mexico (Shultz, 1996) (Fig. 16).

Diagnosis.-Some of the morphological distinctions between Elaphe bairdi and the other members of the E. obsoleta complex have been described in other literature (Olson, 1977; Lawson and Lieb, 1991). However, with Tables 1-2 and 12- 13 and the descriptions in this section, I will expand what is known regarding the morphology of this species. Elaphe bairdi is generally smaller and less robust than E. alleghaniensis, E. spiloides, and E. obsoleta. Adult males have an average SVL of 1004 mm and females have an average SVL of 927 mm. The head is distinct and well differentiated from the body. Like the other Elaphe examined here, it has a laterally-compressed body that is slightly

higher than wide. Very little sexual dimorphism can be found in E. bairdi. Males tend to have more subcaudals and a larger DBL1. Individuals of Elaphe bairdi have eight or nine supralabials, 13 or 14 infralabials, one preocular, and two postoculars. Unlike the other Elaphe examined here, the first keel at midbody begins on the sixth dorsal scale row in adults. This is a diagnostic character for E. bairdi that E. alleghaniensis, E. spiloides and E. obsoleta do not share. Males and females usually have 25, 27, or 29 scale rows at the level of the tenth ventral scale; 25, 27 or 29 scale rows at midbody; and 19 or 21 scale rows at the level of the penultimate ventral scale.

Elaphe bairdi usually has a higher number of ventrals, subcaudals, temporal scales, dorsal blotches, and lateral blotches than the other three species (Tables 1, 2). The size of the DBW1, DBL1, LBW1, and LBL2 is much smaller in this species. The ratio, TL/SV, is also much larger in E. bairdi. The following ratios are smaller in male E. bairdi compared to the other three Ela- phe: PW/HL, PWP/HL, FW/ HL, PRFL/ HL, PRFWA/HL, PRFWP/HL, INWA/ HL, INWP/HL, PG/HL, INR/HL, RH/ HL, RW/HL, PROW/HL, LHT/HL, and LH/HL. These values are similar for females except LHT/HL is not smaller in E. bairdi than in the other three species. The following characters tend to be much larger in both sexes of E. bairdi compared the other Elaphe examined in this paper: PL/ HL, FL/HL, INL/HL, AG/ HL, NR/ HL, PROLD/ HL, LV/HL. The small values for INL/HL, INWA/HL, INWP/HL, INR/ HL, RH/HL, and RW/HL and large values for INL/HL demonstrate that the muzzle in E. bairdi is longer and narrower than E. alleghaniensis, E. spiloides, and E. obsoleta.

Color variation.-Individuals of Elaphe bairdi tend to be more uniformly patterned than the other three species. How- ever, the ground coloration exhibits sub- stantial intraspecific variation. In some individuals, the ground color varies from brown to orange anteriorly, and fades to gray or silver before the tail (Schultz, 1996). In other specimens, a silver or blu-


201 HERPETOLOGICAL- - - MONOGRAPHS 4

ish-purple ground color occurs over the entire length of the body. Two dark dorsal stripes run from the neck to the tail tip and two lateral stripes run from the neck to the level of the cloaca. In some specimens, the stripes and/or blotches are very poorly defined, and when blotches are present, they tend to be very light and difficult to see. Medial ventral blotches usually occur before the first ventral scale in E. bairdi, but do not often occur before the first ventral scale in the other three species of Elaphe examined here. The medial blotches may become diffuse and form two rows that run from midbody to the tail tip. A light postocular mask may be present in some specimens. If barring on the labial scales is present, it is usually light.

Acknowledgments.-I owe a debt of gratitude to my committee members: J. McGuire, M, Fitzsimons, M. Hafner, D. Foltz, F. Sheldon and D. Rossman. J. Slowinski and R. Lawson must be acknowledged for their input on this project. K. Naoki allowed me use of his computer during his absence in the summer of 1999. I am very grateful to the following persons who provided help in obtaining samples used in this study: P. Moler, A. Meier, A. Meier, Jr., G. Burbrink, C. Burbrink, K. Krysko, A. Smythe, A. Bass, G. Clark, C. Armant, G. Watkins, D. Rossman, S. Rossman, E. Censky, W. Gibbons, T. Tuberville, D. Wills, M. Braun, B. Payst, J. Cole, P. Frank, J. Decker, L. Giod- ano, H. Dessauer, E. Liner, W. Shoop, S. Cardiff, J. McLean, W. Sanderson, R. Vaeth, S. Secor, R. Axtel, C. Smith, H. Dowling, R. Knight, G. Schafer, C. Guy- er, D. Hartman, A.Wilson, R. Brandon, F. Scott, M.

Sabaj, M. Waters, S. Trauth, J. Babin, D. Dittmann, V. Remsen, F. Sheldon, C. Phillips, J. Petzing, M. Dreslik, C. Sheil, J. Collins, T. Taggart, J. Boundy, T. Majors and J. Demastes. I am grateful for financial assistance from the California Academy of Sciences In-House Research Fund, the Theodore Roosevelt Memorial Fund, Ernst Mayr Award, and Charles Sterns Grants-in-Aid.

Finally, I wish to thank the following individuals and institutions for loaning numerous specimens re- quired for the completion of this study:

AMNH: American Museum of Natural History: New York: Linda Ford, Darrel Frost

ANSP: Academy of Natural Sciences, Philadelphia: Ted Daeschler, Ned Gilmore

ASUMZ: Arkansas State University, Fayetteville: Stanley Trauth

AUM: Auburn University Museum, Auburn: Craig Guyer, Robert Reed

BCB: Bryce C. Brown Collection, Baylor University, Waco: Frederich Gehlbach, David Lintz

CAS: California Academy of Sciences, San Francisco:

Jens Vindum, Joseph Slowinski CR: Charleston Museum, Charleston: Albert Sanders

CM: Carnegie Museum of Natural History, Pitts- burgh: Ellen Censky, John Wiens, Steve Rogers

FMNH: Field Museum of Natural History, Chicago: Alan Resetar, Harold Voris

INHS: Illinois Natural History Survey, Champaign: Chris Phillips, John Petzing

KU: University of Kansas Museum of Natural His- tory, Lawrence: William Duellman, John Simmons, Chris Sheil

LSUMZ: Louisiana State University Museum of Nat- ural Science, Baton Rouge: Douglas Rossman, Frederick Sheldon, and Donna Dittman

MCZ: Museum of Comparative Zoology, Cambridge: John Cadle, Jose Rosado

MPM: Milwaukee Public Museum, Milwaukee: Rob- ert Henderson, Gary Casper

NCSM: North Carolina State Museum, Raleigh: Al- vin Braswell, Jeffrey Beane

OMNH: Oklahoma Museum of Natural History, Nor- man: Laurie Vitt

SM: Strecker Museum, Baylor University, Waco: Frederick Gehlbach, David Lintz

SREL: Savannah River Ecology Laboratory, Aiken: Whit Gibbons, Tracy Tuberville

TCWC: Texas Cooperative Wildlife Collection, Col- lege Station: Lee Fitzgerald, Kathryn Vaughan

TNHC: Texas Natural History Collection, Austin: Da- vid Cannatella

UF: Florida State Museum, Gainesville: David Auth, Kenney Krysko

UGAMNH: University of Georgia Museum of Nat- ural History, Athens: Elizabeth McGhee

UIMNH: University of Illinois Museum of Natural History, Urbana: Chris Phillips, John Petzing

UNSM: University of Nebraska Science Museum, Lincoln: John Lynch

UTA: University of Texas, Arlington: Jonathan Camp- bell.

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APPENDIX I

Specimens Examined.

Elaphe alleghaniensis (398) Connecticut: Fairfield Co.: AMNH 17447. Hartford Co.: AMNH 119308, 119659, 130608, 130610-1, 134274-5, 136729. Litch- field Co.: AMNH 97248, 125047, 142245. Middlesex Co.: AMNH 125048, 128045. New Haven Co.: AMNH 119309-11, 125049, 125050, 128046, 125051, 134277, 142652. Florida: Alachua Co.: CAS 18200; LSUMZ 7469, 42789, 46945, 58198, 58511; MCZ 19140; UF 2106, 2140, 2149, 2734, 2762-3, 2976, 4791, 8492, 9205, 9825, 12098, 14063, 14206, 14351, 14460-1, 16433, 16460, 19276, 19330-1, 19333, 21677, 34002, 49261, 49264, 49329, 49335, 49344, 49348-9, 4943-4, 49447, 64983, 64987, 64991-2, 64994, 65122, 65546, 65548, 65550, 65554, 65562, 65563, 67532, 70563, 78860, 79974, 113265. Broward Co.: LSUMZ 57697, 57722. Citrus Co.: CAS 169854; LSUMZ 80180; UF 21684, 65551, 113277. Collier Co.: CM 26939, KU 145879, 176726; SM 13441; UF 16442, 21657, 62891, 65559, 73172, 80024, 84482-4, 113280, 113281, 113283, 113284. Columbia Co.: LSUMZ 58509. Dade Co.: ANSP 31324; CAS 204789; CM 37248, 46740, 51024, 66525; FMNH 204110-1; KU 68915; LSUMZ 18973;



MCZ 12519, 31785, 42999, 69125, 180288 R-140321, R-140322; MPM 26221, 26222; UF 19273, 65565, 65567, 113292-3, 113295-9, 113300, 113303, 113924. DeSoto Co.: MCZ 42394. Dixie Co.: CAS 192090; UF 16441, 16445, 54164, 113306, 113307, 113309, 113310, 113312, 113313, 54163A, 54163B. Duval Co.: LSUMZ 58512; MCZ 6865, 96679. Gil- chrest Co.: LSUMZ 28868; UF 12091, 64608, 113349. Glades Co.; MCZ 170334. Hernando Co.: CAS 169468; LSUMZ 59642. Hillsboro Co.: MCZ 6685. Indian River Co.; MCZ 39871-3, 168512. Leon Co.: AMNH 102321. Levy Co.: CAS 175026; FMNH 245680; LSUMZ 7144, 7260, 28986; MCZ 46147-9, 46301, 46302; UF 2824, 11142, 15960, 36522, 64340, 65561, 65565, 113379, 11380-5, 113387, 113396-9, 113400; UGAMNH 6370. Manatee Co.: CAS 192084-5. Marion Co.: MCZ 12972, 12973, 42392. Martin Co.: LSUMZ 58191. Monroe Co.: AMNH 73930; LSUMZ 28870, 34312; MCZ 29335, R- 180277; UF 8609, 64995, 73462, 113421-2. Orange Co.: LSUMZ 80469, 80470, 80471. Palm Beach Co.: LSUMZ 9152, 58192. Pinellas Co.: CAS 17312; MCZ 18982. Polk Co.: CAS 192086. Putnam Co.: LSUMZ 80181-2. Seminole Co.: LSUMZ 2019. Sumter Co.: CAS 173173. Suwannee Co.: UF 74344, 113465. Tay- lor Co.: LSUMZ 57749; UF 113466, 113468-70. Wakulla Co.: CAS 203079; LSUMZ 57748, 58073. Georgia: Baker Co: ANSP 22251. Bleckley Co.: UF 11349-1. Brantley Co.: 113495. Burke Co.: ANSP 30919. Camden CO.: ANSP 31191; UF 73469. Clinch Co.: UF 113502. Cobb Co.: UF 2480. Colum- bia Co.: UF 113497. Decatur Co.: UF 12388. Dekalb Co.: 4839. Emanuel Co.: ANSP 30908, 30920-1; UF 7947. Glynn Co.: ANSP 31051. Grady Co.: UF 73465-7. Harris Co.: UF 16448. Irwin Co.: UF 113496. Liberty Co.: CAS 14117. Lowndes Co.: ANSP 30895; UF 11443. McIntosh Co.: UF 84006. Newton Co.: UF 113499. Rabun Co.: UGAMNH 6259, 6315, 6328-9, 6334. Richmond Co.: UF 16450-1, 113500-1. Screven Co.: 30922. Ware Co.: UF 2107. Maryland: Frederick Co.: LSUMZ 44662. New York: Dutchess Co.: AMNH 120078, 137475, 142938. Orange Co.: AMNH 13777, 38752, 120079; LSUMZ 80471. Putnam Co.: AMNH 130189; CM 58466. Ulster Co.: UF 113524. Westchester Co.: AMNH 130190, 130787, 133024, 136676-7. Syntype of E. alleghaniensis: ANSP 16792. North Carolina: Avery Co.: CAS 192088. Brunswick Co.: CM 21540; NCSM 1541, 2178, 3851, 6367, 12467, 12468, 12527, 12528, 14671, 15026, 15383, 15599, 16773, 17923, 19525, 26248. Carteret Co.: CAS 43683. Cherokee Co.: CM 57174. Macon Co.: NCSM 12771, 13047, 14160, 14161, 14268, 14344, 14345, 15922. Sampson Co.: NCSM 2631, 8100, 10134-5, 10145, 10202-3, 14108, 15418-9, 16599, 16600, 19695, 25881, 26206, 31848, 39571, 41287, 41289. Transylvania Co.: CR 266. Wayah Bald Mt.: CM 39615. Pennsylvania: Cen- ter Co.: LSUMZ 46888. South Carolina: Aiken Co.: CR 2633, MCZ-181268; SREL 126, 170, 1690, 3123, 3132, 3225, 3457-8, 3466, 4218, 4223, 4243, 4246, 4284, 4362, -4; UGAMNH 6313, 6339, 6342, 6348- 9. Bamberg Co.: CR 2640, 3481, 4217. Charleston Co.: AMNH 113049; ANSP 3773; FMNH 4282, 4766; SREL 1101; UGAMNH 6258. Fairfield Co.:

CR 2635. Jasper Co.: LSUMZ 58526. Lexington Co.: CM 16787; CR 2625, 2631; FMNH 60560. Richland CO.: CR 263-4, 2624, 2632, 2634, 2636. Virginia: Bedford Co.: CM 130179, 146302, 146431,146353, 146356, 146358, 146387, 146392, 146446-7, 146463, 146507, 146523-4, 146533, KU 68914.

Elaphe spiloides (312) Alabama: Baldwin Co.: AUM 414, 10310, 10314, 10383, 21011; LSUMZ 57698, 75698; UF 16443. Barbour Co.: UF 19277. Calhoun Co.: AUM 5348, 6525-6, 30795. Cherokee Co.: LSUMZ 33070. Clarke Co.: Aum 12578, 22929- 30. Cleburne Co.: AUM 80, 2991. Coffee Co.: UF 108484. Dale Co.: LSUMZ 6709. Elmore Co.: UF 87565. Lee Co.: AUM 31-3, 415, 430, 766, 1723, 2047, 2091, 2863, 4729, 10385, 13681, 27312, 32509, 32556; LM 9884; LSUMZ 58165, 58446. Macon Co.: LSUMZ 58459. Madison Co.: LSUMZ 41189. Mo- bile Co.: AMNH 123900; ANSP 10893-4, 7798. Monroe Co.: AUM 7133. Pike Co.: UF 108488. Ran- dolph Co.: AUM 8957. Shelby Co.: UF 8499. Talla- dega Co.: AUM 17107, 21608, 21676, 23021; LSUMZ 58527. Washington Co.: AUM 58196. Flor- ida: Escambia Co.: LSUMZ 15915; MCZ 169. Holmes Co.: LSUMZ 6508. Okaloosa Co.: AUM 29748, 30454; UF 16444, 68180, 72663. Santa Rosa Co.: AUM 29746; KU 82074; UF 67921, 113461-2; LSUMZ 58354. Walton Co.: LSUMZ 58196. Illinois: Adams Co.: MCZ 52. Bond Co.: INHS 5166, 8175. Calhoun Co.: INHS 3392, 10614, 11450; UIMNH 16646-7, 50840. Clark Co.: INHS 2598. Clay Co.: INHS 14011. Cole Co.: INHS 10097. Effingham Co.: INHS 3129, 884; MCZ 71839. Fayette Co.: INHS 5165, 12494, 13069. Gallatin Co.: INHS 1384, 14012, 14014. Green Co.: UIMNH 50838. Hamilton Co.: INHS 2266, 2637. Jackson Co.: AUM 2001; CM 114334; FMNH 18655, 18656, 155048, 204022, 204037; INHS 1079, 1081-2, 1807, 2055, 2550, 3858; LSUMZ 58408-9; MCZ 181237, 181238. Jasper Co.: INHS 1299, 1950, 2095, 14039. Jefferson Co.: 9287. Jersey Co.: 1744, 1779, 1780, 9901, 11012-4, 11019, 11023, 11342, 11345, 11448, 11451. Johnson Co.: INHS 13972. Lawrence Co.: INHS 4727. Madison Co.: INHS 11020, 11022; UIMNH 16326, 33943. Monroe Co.: INHS 3689, 4286, 4753. Montgomery Co.: INHS 1301. Perry Co.: INHS 3363, 9899, 9900, 13908. Piatt Co.: INHS 4248. Pike Co.: INHS 3650. Pope Co.: INHS 1386-7, 1388, 2312, 4987. Randolph Co.: INHS 4257. Richland Co.: INHS 14016. St. Clair Co.: INHS 9898, 13453, 13454. Union Co.: FMNH 19262, 195485; INHS 1303, 1304, 1382, 1383, 1647, 2255-7, 5981, 7029, 8089, 10583, 11272; KU 69657; MCZ 181470. Vermillion Co.: INHS 1302, 7028, 9018, 10040, 10288, 10622, 14004, 5221. Wabash Co.: INHS 5221. Washington Co.: INHS 4387. Wayne Co.: INHS 12744. White Co.: INHS 14015. Williamson Co.: INHS 6802. Kentucky: Bal- lard Co.: KU 214415. Calloway Co.: KU 144760, 214413-4. Carlisle Co.: 137763, 214398, 214399. Ful- ton Co.: KU 206538, 214405-6. Grave Co.: KU 214410-1. Hickman Co.: KU 144772, 214416. Mar- shall Co.: KU 14476, 214417. Louisiana: Ascension Par.: LSUMZ 46834. East Baton Rouge Par.: LSUMZ 2832-3, 5857, 6163, 9470, 11888, 11904, 12049, 12257, 12723-5, 12727, 23844, 24795, 33063, 39161,

50 [No. 15 HERPETOLOGICAL MONOGRAPHS


49585, 56148, 56152, 57027, 57686, 57703, 57838, 58193, 58348, 58399, 58407, 59631, 73935. East Fe- leciana Par.: LSUMZ 57744, 58608. Iberville Par.: LSUMZ 6508, 17719, 56497, 57723, 57736-7, 58194-5, 58416, 58229, 58445. St. Charles Par.: LSUMZ 57687. St. Tammany Par.: LSUMZ 58521, 80221. Tangipahoa Par.: LSUMZ 57695, 58163. Michigan: Eaton Co.: CAS 74407. Mississippi: For- rest Co.: LSUMZ 57688. Hancock Co.: CM 66533- 4; MMNS 3478, 3482, 3533, 3540. Harrison Co.: UF 16439-40, 16458. Pearl River Co.: MMNS 3205, 3467, 3486, 3494, 3497-8, 3503, 3548. Smith Co.: LSUMZ 57721; UF 89487. Wilkinson Co.: LSUMZ 57691. Ohio: Montgomery Co.: LSUMZ 58525, 59625. Scioto Co.: INHS 9013. Pennsylvania: Alle- gheny Co.: CM 774, 1620, 1764, 1966, 1976, 4004, 5124, 9923, 11457, 20097, 27075, 31395, 35329, 35709, 140186. Tennessee: Cumberland Co.: LSUMZ 58529. Decatur Co.: LSUMZ 57735. Har- deman Co.: CM 19897. Knox Co.: LSUMZ 58162, 58414, 58510, 59639. Lawrence Co.: CM 19900. Montgomery Co.: LSUMZ 58563. Morgan Co.: INHS 13276. Wisconsin: Crawford Co.: MPM 2035, 2061. Grant Co.: CM 70347. Iowa Co.: MPM 8805. LaCrosse Co.: MPM 23355. Richland Co.: CM 75864; MPM 2027. Sauk Co.: MPM 2137.

Elaphe obsoleta (254) Arkansas: Baxter Co.:AS- UMZ 22353. Benton Co.: LSUMZ 73966. Clark Co.: ASUMZ 22692. Craighead Co.: ASUMZ 22689. Gar- land Co.: ASUMZ 22354, 22694. Lawrence Co.: AS- UMZ 22695. Logan Co.: ASUMZ 22693. Madison Co.: LSUMZ 80246. Mississippi Co.: ASUMZ 22270. Poinsett Co.: ASUMZ 22690-1. Sevier Co.: LSUMZ 74497. White Co.: FMNH 37543; MPM 14371, 15705, 18632, 18846, 18903, 19101, 20712, 21501. Kansas: Barber Co.: KU 193399, 211379. Bourbon Co.: KU 2432. Cowley Co.: KU 179036, 206174, 216190. Douglas Co.: Ku 2424, 2429-31, 2433-4, 2436-8, 2442-8, 2450-3, 2456-60, 2725, 2728, 7557, 28765, 38678, 153039, 188712, 207295. Geary Co.: CAS 38678; LSUMZ 58530. Harper Co.: FMNH 95158; KU 186004. Sumner Co.: KU 18886, 206231- 33, 206400, 206490; LSUMZ 58607. Louisiana: Aca- dia Par.: LSUMZ 58164, 74128. Bossier Par.: LSUMZ 58443; LSUS 4285; UTA 28252. Caddo Par.: LSUS 1322, 2944, 5562, 5823, 5825, 5951, 5991, 6222, 6606; SM 10413, 10415. Lafayette Par.: LSUMZ 73888, 73897, 73911, 73954, 73955, 73956, 73958, 74112, 74122, 74495. Livingston Par.: LSUMZ 58345. Natchitoches Par.: LSUMZ 58995-7. Point

Coupee Par.: LSUMZ 57768. Rapides Par.: LSUMZ 58471. St. Landry Par.: LSUMZ 58230, 73965, 73973, 74098, 74116, 74137, 73895, 73948, 73959, 73975, 73977, 73978, 73981, 74101, 74103. Terrebonne Par.: LSUMZ 59418. Vermillion Par.: LSUMZ 59643. Mis- souri: Butler Co.: INHS 10363. Douglas Co.: INHS 10586. Green Co.: CAS 162004. Nebraska: Cass Co.: UNSM 2236, 8336. Gage Co.: UNSM 549, 552, 1408, 1439, 1446, 1840, 6817, 8337. Johnson Co.: UNSM 2241. Nemaha Co.: UNSM 2237, 2238. Otoe Co.: UNSM 2244, 8335. Pawnee Co.: UNSM 7266. Rich- ardson Co.: UNSM 550, 553, 1839, 3981. Saunders Co.: UNSM 15456. Thayer Co.: UNSM 2242. Oklahoma: Cleveland Co.: OMNH 550, 642, 2894,

3751, 5584, 5882, 8105, 8816, 10136, 13361, 15064, 15081, 18978, 20207, 20209, 20211, 23195, 23247, 23362, 26970, 28605, 29944, 33967, 67163. Tulsa Co.: CM 61916. Texas: Bexar Co.: AMNH 73366; ANSP 12129; CAS 30972-3, 31099-100; CAS-SU 17750-1; CM 22849; FMNH 3510; TCWC 42310; TNHC 55330. Brazos Co.: SM 10428. Kerr Co.: TCWC 205, 7240, 31069. Medina Co.: CM 19918; TCWC 38779, 42872; TNHC 42246; UTA 32197. Orange Co.: LSUMZ 80184. Robertson Co.: TCWC 6105. Tarrant Co.: UTA 7734, 8733, 10941, 14710, 17103, 19329, 25710, 26467, 26468, 28696, 28697-99. Travis Co.: TNHC 98, 610, 947, 1632, 1705, 2020-1, 4584, 5245, 5251-2, 5949, 7230, 7243, 8786, 9147, 10265, 10267, 18535-6, 21881, 22421, 29091-2, 36336, 42247-9, 42681, 42788, 43104, 46274, 47182, 47222, 49948. Uvalde Co.: TNHC 47636. Washington Co.: CR 429. Mexico: Nuevo Leon: SM 8180-Collecting locality is probably in error (E. Liner, pers. corn.).

Elaphe bairdi (32) Texas: Bandera Co.: SM 104536; TCWC 79951; TNHC 25467. Boswue Co.: TCWC 36939. Brewster Co.: FMNH 26619, 27703, 27844; SM 746, 12107. Jefferson Davis Co.: AMNH 115718; CAS 7509; FMNH 27704; LSUMZ 58523- 4; TCWC 42858, 66184; TNHC 33616. Kerr Co.: TCWC 42857, 67282. Medina Co.: TCWC 48595, 48596. Pecos Co.: SM 13445. Real Co.: TCWC 30762. Val Verde Co.: LSUMZ 34527, 44461; SM 13272; TCWC 60528, 71050, 77161-2, 79746; TNHC 49251.

APPENDIX II

List of Morphological Characters Used in this Study

Length always refers to measurements made longi- tudinally to the long axis of the body and width always refers to measurements made transversely to the long axis of the body.

Meristic Measurements

1. Ventrals (V). Total number of ventral scales beginning with the first scale row that contacts the first dorsal scale on both sides of the venter and not including the anal plate (Dowling, 1951).

2. Subcaudals (SC). Total number of subcaudals on one side, beginning with the first scale behind the vent that contacts a subcaudal from the other side. The terminal spine is not included (Ross- man et al., 1997).

3. Supralabials Left (SLL). Supralabials on the left side of the head are counted from the first scale posterior to the rostral scale along the mouth to the last enlarged scale bordering the gape.

4. Supralabials Right (SLR). Supralabials on the right side of the head are counted from the first scale posterior to the rostral scale along the mouth to the last enlarged scale bordering the gape.

5. Infralabials Left (ILL). Infralabials on the left side of the head bordering the mouth are counted from the first labial posterior to the anterior genial scale to the last enlarged scale bordering the gape.

6. Infralabials Right (ILR). Infralabials on the right

51 2001] HERPETOLOGICAL MONOGRAPHS


side of the head bordering the mouth are counted from the first labial posterior to the mental scale to the last enlarged scale bordering the gape.

7. Preocular Left (PROL). Number of preocular scales on the left side of the head.

8. Preocular Right (PROR). Number of preocular scales on the right side of the head.

9. Postocular Left (POL). Number of postocular scales on the left side of the head.

10. Postocular Right (POR). Number of postocular scales on the right side of the head.

11. Temporals Left (TML). Number of temporal scales on the left side of the head. Omitting the postocular scales, they include all scales found between the parietal scale and the supralabial scales.

12. Temporals Right (TMR). Number of temporal scales on the right side of the head. Omitting the postocular scales, they include all scales found between the parietal scale and the supralabial scales.

13. Dorsal Scale Row 10 (DSR10). Number of dorsal scales around the body, beginning at the tenth ventral scale.

14. Dorsal Scale Row at midbody (DSR 50). Number of dorsal scales around the body starting at the midbody ventral scale.

15. Dorsal Scale Row Penultimate (DSRPEN). Number of dorsal scale rows around the body counted at the level of the penultimate ventral.

16. Keel (K). The first dorsal scale row at midbody that exhibits a keel.

17. Dorsal Blotch Number (DB). Number of dorsal body blotches counted from the neck to the level of the vent.

18. Lateral Blotch Number (LB). Number of lateral body blotches counted from the neck to the level of the vent.

19. Wide Dorsal Blotch Width (DBW1). The number of scales counted transversely in widest part of the dorsal blotch at midbody.

20. Narrow Dorsal Blotch Width (DBW2). The number of scale rows counted linearly in narrowest part of the dorsal body blotch at midbody.

21. Long Dorsal Blotch Length (DBL1). The number of scales rows counted transversely in the longest part of the dorsal body blotch at midbody.

22. Short Dorsal Blotch Length (DBL2). The number of scale rows counted linearly in the shortest part of the dorsal body blotch at midbody.

23. Wide Lateral Blotch Width (LBW1). The number of scale rows counted transversely in the widest part of the lateral body blotch at midbody.

24. Narrow Lateral Blotch Width (LBW2). The number of scale rows counted transversely in the narrowest part of the lateral body blotch at midbody.

25. Long Lateral Blotch Length (LBL1). The number of scale rows counted linearly in the longest part of the lateral body blotch at midbody.

26. Short Lateral Blotch Length (LBL2). The number of scale rows counted linearly in the shortest part of the lateral body blotch at midbody.

27. Dorsal Stripe Width (DSW). Number of scale rows counted transversely across the dorsal body stripe.

28. Lateral Stripe Width (LSW). Number of scale rows counted transversely across the lateral body stripe.

29. Supralabial Bars (SLBN). Number of barred or marked supralabials on the left side of the head.

30. Infralabial Bars (ILBN). Number of barred or marked infralabials on the left side of the head, not including supralabials darkened by the postocular stripe

31. Lateral Ventral Blotch Number (VBLAT). The anterior-most ventral that contains a lateral ventral blotch.

32. Medial Ventral Blotch Number (VBMED). The anterior-most ventral that contains a medial ventral blotch.

Mensural Characters

33. Snout-Vent Length (SV). Measured from the anterior rostral tip to the posterior margin of the anal plate.

34. Tail Length (T). Measured from the posterior margin of the anal plate to the tip of the tail spine.

35. Head Length (HL). Measured from the rostral tip to the posterior apex of the retroarticular process of the compound bone.

36. Parietal Length (PL). Length of the parietal measured along the median suture from the posterior most point of contact with the frontal scale to the point of contact with nuchal scales.

37. Anterior Parietal Width (PW). Measured from the contact point of the median suture with the posterior-most extension of the frontal scale to the point where the parietal contacts the ventral most postocular scale and the most ventral temporal scale in the first temporal scale row.

38. Posterior Parietal Width (PWP). Measured at the narrowest posterior point in contact with nuchal scales.

39. Frontal Length (FL). Measured medially from the posterior suture point between prefrontals to the posterior apex of the prefrontals.

40. Medial Frontal Width (FW). Measured from right supraocular-frontal contact to the left supraocular-frontal contact located midway between the anterior-most point and posterior-most point of the frontal scale.

41. Posterior Frontal Width (FWP). Measured across the posterior margin of frontal scale from the contact point with the right surpaocular-parietal suture to the contact point with the left supraocular-parietal suture.

42. Anterior Frontal Width (FWA) Measured across the anterior margin of the frontal from the contact point with the right supraocular-prefrontal suture to the contact point with the left supraocular-prefrontal suture.

43. Prefrontal Length (PRFL). Measured along the median suture from the posterior- most contact point with the frontal to the anterior-most contact point with internasal.


20011 HERPETOLOGICAL MONOGRAPHS 53

44. Anterior Prefrontal Width (PRFWA). Measured on the left prefrontal from the anterior prefrontal median suture connection with the internasal to the dorsal-and the anterior-most connection with the loreal.

45. Posterior Prefrontal Width (PRFWP). Measured on the left prefrontal from the posterior prefrontal median suture connection with the frontal to the point of contact with the loreal-preocular suture.

46. Internasal Length (INL). Measured along the median suture from the posterior connectio with the prefrontal to the anterior connection with the rostral.

47. Anterior Internasal Width (INWA). Measured on the left internasal from the median suture connection with the rostral to the point of contact with the anterior nasal-posterior nasal suture.

48. Posterior Internasal Width (INWP). Measured on the left internasal from the median suture contact with the prefrontal scale to the dorsal- and posterior-most contact with the posterior nasal.

49. Eye Diameter (EYE). Measured at the widest horizontal point between preocular and postocular.

50. Anterior Genial Length (AG). Measured from the anterior most point of contact with the supralabials to the posterior most contact with the gular scales.

51. Posterior Genial Length (PG). Measured from the anterior most point of contact with the anterior genial to the posterior most point of contact with the posterior genial scale.

52. Internasal Rostral Contact (INR). Measured across the width of contact between both inter- nasals and the rostral scale.

53. Nasal Rostral Contact (NR). Measured along the anterior nasal contact with the rostral scale from the contact point with the dorsal internasal-rostral suture to the supralabial-rostral suture.

54. Rostral Height (RH). Measured from the rostral contact with the internasal median suture to the left ventral-most extension of the rostral scale.

55. Rostral Width (RW). Measured from the left rostral contact point with the anterior nasal-supralabial suture to the contact point with the right anterior nasal-supralabial suture.

56. Posterior Nasal Length (PNL). Measured along the supralabial-posterior nasal suture from the posterior nasal contact point with the supralabial- loreal suture to the contact point with the anterior nasal-supralabial suture.

57. Anterior Nasal Length (ANL). Measured along the supralabial-anterior nasal suture from the contact point with the supralabial-posterior nasal suture to the contact point with the supralabial- rostral suture.

58. Preocular Width (PROW). Height of the preocular measured from the dorsal-most contact with supraocular-frontal-prefrontal sutures to the ventral-most contact with the supralabials.

59. Dorsal Preocular Length (PROLD). Measured from the contact with the loreal-prefrontal sutures straight across the preocular to the contact with the eye.

60. Ventral Preocular Length (PROLV). Measured from the preocular contact point with the loreal- supralabial suture to the contact point with eye and supralabial suture.

61. Dorsal Loreal Length (LD). Measured from the loreal contact point with the posterior nasal-prefrontal suture to the contact point with prefrontal-preocular suture.

62. Ventral Loreal Length (LV). Measured from the loreal contact point with the posterior nasal-supralabial suture to the preocular-supralabial suture.

63. Loreal Height (LHT). Width of the loreal measured from the loreal contact point with the posterior nasal-supralabial suture to the contact point with the anterior nasal-prefrontal suture.

64. Supralabial Length (LL). Measured from the posterior-most contact with the dorsal body scales to the anterior most contact with the rostal scale.

65. Supralabial Height (LH). Width of the largest supralabial scale (usually the seventh or eight supralabial scale) measured from the ventral margin to the dorsal-most contact point with the temporal scale sutures.

66. First Dorsal Scale Length (DSR1). Measured on one dorsal scale in the first dorsal scale row at midbody.

67. Vertebral Row Dorsal Scale Length (VR). Mea- sured on one vertebral scale taken at midbody in the vertebral scale row.


systematics of the eastern ratsnake complex (elaphe obsoleta)

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