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GOPHER TORTOISE DEMOGRAPHY 289

MCRAE,W. A., J. L. LANDERS,AND G. D. CLEVELAND. gopher tortoise (Gopherus polyphemus) in north- 1981a. Sexual dimorphism in the gopher tortoise central Florida. Bull. Florida State Mus. Biol. Sci. (Gopheruspolyphemus). Herpetologica 34:46-57. 28:79-102. , ANDJ. A. GARNER.1981b. Movement TURNER, F. B., C. G. THELANDER,D. C. PEARSON,AND patterns and home range of the gopher tortoise. B. L. BURGE.1982. An evaluation of the transect Amer. Midi. Natur. 106:165-179. technique for estimating desert tortoise density at SCHNEIDER,P. B. 1980. A comparison of three meth- a prospective power plant site in Ivanpah Valley, ods of population analysis of the desert tortoise, California. In K. A. Hashagen (ed.), Desert Tortoise Gopherusagassizii. In K. A. Hashagen (ed.), Desert Counc. Symp. Proc. 1982:134-153. Tortoise Counc. Symp. Proc. 1980:156-162. WESTER,E. E. 1986. Demography of two insular pop- SHIELDS,T. A. 1980. A method for determination of ulations of the gopher tortoise, Gopheruspolyphe- population structure and density of the desert tor- mus (Daudin), in a reservoir in southwestern Geor- toise. In K. A. Hashagen (ed.), Desert Tortoise gia. Unpubl. M.S. Thesis, Auburn Univ., Auburn, Counc. Symp. Proc. 1980:151-155. Alabama. 57 pp. STOUT, I. J., T. J. DOONAN,R. E. ROBERTS,AND D. R. WILSON,D. S. 1991. Estimates of survival for juvenile RICHARDSON.1989. A comparison of three go- gopher tortoises, Gopheruspolyphemus. J. Herpetol. pher tortoise relocations in central and southeast 25:376-379. Florida. In J. E. Diemer, D. R. Jackson, J. L. Landers, WRIGHT, S. 1982. The distribution and population J. N. Layne, and D. A. Wood (eds.), Proc. Gopher biology of the gopher tortoise (Gopheruspolyphe- Tortoise Relocation Symp., pp. 15-42. Florida Game mus) in South Carolina. Unpubl. M.S. Thesis, and Fresh Water Fish Comm., Nongame Wildl. Clemson Univ., Clemson, South Carolina. 74 pp. Prog. Tech. Rep. No. 5., Tallahassee. TAYLOR,R. W., JR. 1982. Human predation on the Accepted: 1 May 1992.

Journalof Herpetology, Vol. 26, No. 3, pp. 289-292, 1992 Copyright 1992 Society for the Study of Amphibians and

An Unusual New Sphaerodactylus from Hispaniola (:Gekkonidae)

RICHARDTHOMAS' AND S. BLAIRHEDGES2

'BiologyDepartment, University of PuertoRico, Rio Piedras, Puerto Rico 00931-23360, USA, and 2Departmentof Biology,208 MuellerLab, Pennsylvania State University, UniversityPark, Pennsylvania 16802, USA

ABSTRACT.-A new of Sphaerodactylusis described from xeric limestone scrub of the Barahona Peninsula of Hispaniola. Its combination of small body size and very large, flattened, keeled dorsal scales distinguish it from other species in the .

Five of the 82 species in the lizard genus the west-central portion of the peninsula. In Sphaerodactylusare known from lowlands of the that habitat, we recently found a small Sphae- Barahona Peninsula in southwestern Domini- rodactylus that is one of the most distinctive can Republic (Schwartz, 1977): S. difficilis Bar- members of the genus. After Nicholas Plum- bour, S. armstrongi Noble and Hassler, S. randi mer, who helped collect the type series, we pro- Shreve, S. streptophorusThomas and Schwartz, pose the name and S. thompsoni Schwartz and Franz. Sphaero- nov. dactylus is found only along the more Sphaerodactylusplummeri sp. difficilis 1A mesic eastern margin of the peninsula, and S. Fig. armstrongi is a species of the eastern mesic low- Holotype.-USNM (United States National lands as well as uplands throughout the Sierra Museum) 317892, an adult female, from 10.6 km de Baoruco. Localities for the remaining three N Cabo Rojo on the Alcoa road (2.6 km N Ped- lowland species are predominantly in eastern ernales-Oviedo road), Pedernales Province, Do- and western parts of the peninsula (Schwartz minican Republic, elevation 80 m, 28 July 1991, and Henderson, 1991). Although two species, one of a series collected by Nicholas Plummer, S. streptophorusand S. thompsoni,are known from S. Blair Hedges, and Richard Thomas. xeric habitats, no Sphaerodactylusis known from Paratopotypes.-USNM 317893-901, same data the extremely xeric limestone platform scrub of as holotype. 290 R. THOMAS AND S. B. HEDGES

A

4

C

FIG.1. Three species of Sphaerodactylusfrom the BarahonaPeninsula of Hispaniola: (A) S. plummeri(21 mm SVL;Dominican Republic,Pedernales, 10.6 km N Cabo Rojo);(B) S. streptophorus(22 mm SVL;Dominican Republic,Pedernales, Hoyo de Pelempito);and (C) S. armstrongi(24 mm SVL;Dominican Republic, Pedernales, 44.6 km N Cabo Rojo). UNUSUAL NEW 291

Diagnosis.--A small, short, but acute-snouted lower postnasal, small, granular. First upper la- species of Sphaerodactylus(18-22 mm SVL, snout- bial roughly pentagonal, emarginate on ante- vent length) with large, flattened, keeled, im- rior half of upper edge, high point about mid- bricate dorsal body scales and unusually large way along scale; second and third (to mideye) cobblelike (broad, rounded, and raised) snout narrow rectangles. Eyelid spine well devel- scales (snout averages 36% head length); with oped; pupils round to oval with narrow pale only two toe pad bracket scales; a four-lined edge. Mental subpentagonal (rounded anteri- head pattern, with the two postocular lines ex- orly) with two large subpentagonal or subhex- tending onto the body as dorsolateral and mid- agonal postmentals followed by a short zone of flank stripes (indistinct in most specimens); and large flat, smooth, cobblelike gulars quickly with minute prescapular ocelli in line with the changing to smaller, more granular but imbri- head stripes. cate scales on throat (gulars between the ear = Sphaerodactylusplummeri is unique in several openings 22-38, x = 33.8 + 1.53, n 10); be- respects: it has the lowest dorsal and midbody coming flattened and imbricate on posterior scale counts of any Hispaniolan species (among throat; a few anterior gulars weakly keeled, the the lowest of any species); the snout scales are rest smooth. First lower labial subrectangular, the largest (with the exception of S. elasmorhyn- somewhat wider anteriorly, the second sub- chus); it has only two toe pad bracket scales triangular, and the third small and narrow (only one other species of Sphaerodactylusthat (roughly pentagonal). Snout scales very large we have examined has fewer than three); and (broad, rounded, swollen), smooth (weak keels females undergo ontogenetic head pattern on upper snout), and slightly imbricate (scales modification in which the striped pattern be- between 1st interlabial sutures 7-10, x = 9.1 + comes broken into spots. 0.38, n = 10); usually with at least two enlarged Sphaerodactylusstreptophorus (Fig. 1B) is a small, snout scales, most specimens with an enlarged dark or dull-colored species and superficially scale behind supranasal and upper postnasal on resembles S. plummeri;however, it is larger than each side; snout scales becoming narrower be- S. plummeriwith a maximum SVL of 26 mm. The tween eyes, more symmetrically granular but two differ in details of coloration: S. s. strepto- loping upwards on top of head, more conical phorus, the Barahona Peninsula subspecies, has on neck, flattening onto trunk and becoming a pale transverse collar across the neck, no dor- large, flat, imbricate, acute to slightly mucro- solateral lines, and much smaller body scales nate, and strongly keeled; no middorsal zone (midbody scales 41-62: Thomas and Schwartz, of granules or granular scales; dorsal scales ax- 1983); it also has smaller snout scales and three illa to groin 17-21 (x = 18.1 + 0.46, n = 10); toe pad bracket scales. A larger species, S. arm- dorsal scales reducing in size on lower sides strongi (Fig. 1C), occurs in the upper elevations before transition to ventrals. Pectoral and ven- of the Sierra de Baoruco and Massif de la Selle tral scales smooth, flat, angled to rounded, ven- = (it occurs at higher elevations on the Alcoa road). trals axilla to groin 22-24 (x = 22.4 + 0.36, n = Although it is dark like S. plummeri,S. armstrongi 10); scales around midbody 34-36 (x 35.1 + = usually has Y or V-shaped markings on the head, 0.31, n 10). Unregenerated dorsal scales of tail various ocelli on the body, and has a much acute, keeled, slightly swollen, flat-lying, im- greater number of midbody scales (49-75; Tho- bricate, and verticillate; ventral caudals larger, mas and Schwartz, 1983). Sphaerodactylusrandi more rounded on posterior edge, smooth and also is a larger species with smaller scales; its flat with midventral row enlarged. Escutcheon basic pattern involves the trilineate head pat- prominent and well developed with large cen- tern (as in difficilis), a dark scapular patch, and tral area extending onto posterior abdomen and a pair of ocelli. We compare S. plummeri with broad extension well onto thigh (6 x 15-20). these species because they occur in the area and Toe pad moderately expanded, wider than ad- might be confused with plummerion superficial jacent phalangeal segment; two toe pad bracket examination. scales; subdigital lamellae of fourth digit 9-11 Description.-Size of adults 18 to 22 mm SVL (x = 10.1 + 0.19, n = 10); 10-12 single hair- (x = 20.1 + 0.52 [SE], n = 8). Snout short and bearing scale organs along free edge of dorsal acute; rostral broadly rounded (wider than long), scale. with a semicircular depressed flat area set off Coloration.-Basic pattern (females, juveniles, by a sharply-defined but low ridge before the and immature males), a pair of narrow, pale peripheral declivity; median cleft extends to upper postocular stripes on each side of head ridge; ridge extends onto supranasals; one large, becoming indistinct on body; a median pale usually subpentagonal internasal, barely in- stripe on head ending at occiput; minute postoc- denting rostral, flanked by short, pentagonal cipital ocelli within each of three dorsal-most but roughly triangular supranasals. Upper post- stripes, the median one terminating. Each up- nasal short, oblong, oriented dorsoposteriorly; per postocular stripe proceeding beyond ocel- 292 R. THOMAS AND S. B. HEDGES lus to another minute prescapular ocellus then derson, 1991). Both species occur syntopically continuing onto trunk as indistinct dark-edged at a nearby locality to the west, and we recently stripes with centers the same hue as the ground collected both species in the Hoyo de Pelem- color. Lower edge of dorsolateral stripe more pito, a large topographic depression just south continuous and forming dark dorsal margin of of the Sierra de Bahoruco (in Pedernales Prov- midlateral stripe on each side; lower postocular ince) and northeast of the type-locality of S. stripe continues past forelimb as midlateral plummeri. Sphaerodactylus streptophorus also is stripe. Dorsolateral dark stripes (upper edges of known from localities on the east coast of the dorsolateral stripes) crossing sacral region, Peninsula, near Juancho. However, no species somewhat intensified; a bridge of black pig- of Sphaerodactylusis known from the central ment between the two stripes just past sacrum portion of the limestone escarpment northeast with two tiny included ocelli in-line with stripes of Cabo Rojo. It is possible that S. plummerihas (well developed in USNM 317892); stripes con- evolved in situ on the limestone escarpment tinue onto tail (both upper and lower stripes). and is distributed throughout that formation. Forelimbs with dark brown marbling; a small If that is the case, then it is remarkable that this elbow ocellus often present; hindlimbs with species has not been taken previously along the prominent knee ocelli, other contrasting mar- Alcoa Road or the Oviedo-Pedernales Road, both bling, and a prominent, dark posterior thigh of which have been frequented by collectors in line continuous with dark ventrolateral tail line. the past. Throats with a series of about three patterned thank Nicholas Plum- curved dark lines from Acknowledgments.-We posteriorly converging mer for field Emilio Bautista and each side of Two adult females assistance; Glo- jaw. (USNM ria Santana of the Division of De- 317896, one with head Wildlife, 317899), egg-bearing, of of obscured also partment Agriculture the Dominican pattern by ontogenetic spotting for to collect and with throat lines. In life, Republic permission export spotting obscuring and Linda Maxson for color brown to brown with dark specimens; providing ground gray some facilities. This research was brown to black Two males with uni- supported by markings. from the National Science Foundation dull heads in life; bodies with grants formly yellow 8906325 and REU to the scattered lines indicated or ab- (BSR supplements) ju- flecking, weakly nior author. sent; throats unpatterned or with only faint in- dications of lines; venters hazily stippled with LITERATURECITED pigment. DE LA FUENTE S. 1975. Domini- Remarks.-Because of its unusual scalation, S. GARCIA, Geografia cana. Editorial S. A., Santo is not in known Colegial Quisqueyana, plummeri easily placed any spe- Domingo. 272 pp. + appendix (91 pp.). cies of it shares group Sphaerodactylus.However, HASS, C. A. 1991. Evolution and biogeography of some pattern features with species of the difficilis West Indian Sphaerodactylus(Sauria: Gekkonidae): complex (e.g., the lineate dorsal head pattern), a molecular approach. J. Zool. (London) 225:525- and therefore it might be placed, tentatively, in 561. the large notatus group of the argusseries (Hass, SCHWARTZ,A. 1977. The geckoes (Sauria, Gekkoni- 1991). dae) of the genus Sphaerodactylusof the Dominican Peninsula de Barahona, Proc. Biol. Soc. The specimens of S. plummeriwere taken from Hispaniola. dead and other litter that had Washington 90(2):243-254. agaves vegetation , AND R. W. HENDERSON.1991. accumulated at the base of road cuts the Amphibians along and Reptiles of the West Indies: Dis- Alcoa road in habitat. The lo- Descriptions, very xerophytic tributions, and Natural History. Univ. of Florida cality lies on a large limestone escarpment lo- Press, Gainesville, Florida. 720 pp. cated in the west-central portion of the Baraho- THOMAS,R., ANDA. SCHWARTZ.1983. Part 2. Sphae- na Peninsula which receives <750 mm of annual rodactylussavagei, S. cochranae,S. darlingtoni,S. strep- rainfall (de la Fuente Garcia, 1975). It is pri- tophorus,and conclusions. In A. Schwartz and R. marily exposed and highly dissected limestone Thomas, The difficilis complex of Sphaerodactylus of Bull. with xerophytic vegetation growing directly on (Sauria, Gekkonidae) Hispaniola. Carnegie rock. Mus. Nat. Hist. 22:1-60. and S. Sphaerodactylusstreptophorus thompsoni Accepted: 1 1992. have been taken elsewhere on the Barahona May Peninsula in xeric habitats (Schwartz and Hen-