Norntates PUBLISHED by the AMERICAN MUSEUM of NATURAL HISTORY CENTRAL PARK WEST at 79TH STREET, NEW YORK, N.Y
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AMERICANt MUSEUM Norntates PUBLISHED BY THE AMERICAN MUSEUM OF NATURAL HISTORY CENTRAL PARK WEST AT 79TH STREET, NEW YORK, N.Y. 10024 Number 2918, pp. 1-41, figs. 1-24, tables 1-3 June 28, 1988 Revision of the West Indian Emydid Turtles (Testudines) MICHAEL E. SEIDEL' ABSTRACT The systematics ofemydid turtles, genus Trach- granti (Barbour and Carr), T. d. plana (Barbour emys, in the West Indies is analyzed using external and Carr)-are placed in the synonymies of T. morphology, osteology, and biochemical data. Re- terrapen, T. d. angusta, and T. d. decussata, re- sults indicate the presence of seven recognizable spectively. The description of each valid taxon taxa: T. terrapen in Jamaica and the northern Ba- includes a complete synonymy, new diagnostic hamas, T. decorata on Hispaniola, T. stejnegeri characters, distribution, and ecological notes. Also stejnegeri in Puerto Rico, T. s. vicina on Hispan- included are a taxonomic key and discussion of iola, T. s. malonei on Great Inagua (southern Ba- possible evolutionary origins. Phylogenetic evi- hamas), T. decussata decussata in Cuba, and T. d. dence suggests that the West Indian segment of angusta in Cuba and the Cayman Islands. Three Trachemys is paraphyletic and therefore does not previously described taxa-T. felis (Barbour), T. constitute a natural taxonomic complex. RESUMEN La taxonomia de las tortugas emydid del genero d. plana (Barbour y Carr)-estan puestas en si- Trachemys de Las Indias Occidentales esta analy- nonimias de T. terrapen, T. d. angusta y T. d. zada usando morfologia externa, osteologia, y da- decussata, respectivamente. La descripcion de cada tos bioquimicos. Se reporta la indicacion de la taxon valido incluye un sinonimia completo, nue- presencia de siete taxa reconocible: T. terrapen en vo genio diagnostico, distribucion, y notas eco- Jamaica y en el norte de las Bahamas, T. decorata logicas. Tambien incluido, hay una taxonomia por in Espaniola, T. stejnegeristejnegerien Puerto Rico, clave y discusion de posible origens evoluciona- T. s. vicina en Espaniola, T. s. malonei en Gran rios. La evidencia sugire que la seccion de Trach- Inagua (al sur de las Bahamas), T. decussata emys de Las Indias Occidentales tiene dos evo- decussata en Cuba, y T. d. angusta en Cuba y las luciones (paraphyletic) y por lo tanto no constituye Islas de Gran Cayman. Tres taxa descritas antes- una taxonomia compleja natural. T. felis (Barbour), T. granti (Barbour y Carr), y T. I Professor, Department of Biological Sciences, Marshall University, Huntington, West Virginia 25701. Copyright © American Museum of Natural History 1988 ISSN 0003-0082 / Price $5.25 2 AMERICAN MUSEUM NOVITATES NO. 2918 INTRODUCTION Freshwater or semiaquatic turtles that in- as, 1975) or as few as one (Wermuth and habit the West Indies belong to the slider Mertens, 1961, 1977; Rivero, 1978; and Obst, genus Trachemys (Seidel and Smith, 1986), 1983). Taxonomic recognition ofthe Baham- family Emydidae. Their behavior is typical ian populations has remained especially con- of the widely distributed continental species, troversial (Wermuth and Mertens, 1961; T. scripta. They are opportunistic aquatic Williams, 1956). Schwartz (1978) suggested omnivores with well-developed basking hab- that all Antillean emydids are conspecific ex- its; they utilize diverse aquatic habitats but cept for a second distinct species (Trachemys become terrestrial during dry periods. Al- decorata) on Hispaniola. Contributing to the though their congeneric relationship to T. confusion has been frequent use of labile scripta is evident from similarities in cranial taxonomic characters, including coloration and carapace morphology (McDowell, 1964; and markings, which in some cases were de- Seidel and Smith, 1986), specific identities scribed from nonliving specimens. Problems and distributions have remained poorly of identification are compounded by a wide- understood. Pregill (1981 a) stated that turtles spread tendency for West Indian Trachemys are perhaps the least-studied vertebrates in to lose their markings as they reach maturity the West Indies. Collectively, the West In- and to develop pronounced melanism in adult dian Trachemys forms a geographically dis- males. Although the extent of species diver- crete but taxonomically confused assem- gence and geographic distribution has re- blage. The present study was undertaken to mained uncertain, it appears that all taxa are define more clearly the systematics and dis- allopatric (Seidel and Inchaustegui Miranda, tribution of these species. 1984). Boulenger (1889) considered all West In- Bickham and Baker (1976a, 1976b) ex- dian emydids conspecific with T. scripta. Bar- amined G- and C-band karyotypes and found bour and Carr's (1940) treatise, recognizing no variation in the subfamily Emydinae, in- nine forms and six species in the Greater An- cluding several species of West Indian tilles and Bahamas, has remained the only Trachemys. Recently, Seidel and Adkins comprehensive taxonomic analysis of these (1987) described biochemical divergence freshwater turtles. In 1941 these authors de- among the West Indian Trachemys. The scribed an additional species from the Cay- present systematic review, based on mor- man Islands. Although their analysis was phological analysis of over 500 specimens thorough, Barbour and Carr (1940, 1941) were (living and preserved), reevaluates species re- limited by the small number of available lationships among these turtles, and provides specimens. They stated "It would be foolish new taxonomic characters for diagnoses. No- to say that the last word concerning the sys- menclature, descriptions, geographic distri- tematic status ofthe various West Indian ter- butions, and a proposed phylogeny (based on rapins is said in this paper .... We lack ma- morphological and biochemical characters) terial from too many areas to do more than are also presented. sketch an outline" (Barbour and Carr, 1940: 381). Grant (1948) emphasized the inade- ACKNOWLEDGMENTS quate sample sizes employed by Barbour and Field collections (MES) in the West Indies Carr (1940, 1941) and indicated that reliable were made possible by permits granted by partitioning of the West Indian emydids Joseph Parsons and John McLean, Depart- would require examination of many more ment of Agriculture and Natural Resources, specimens. In the absence ofany other broad Cayman Island, B.W.I.; S. J. Inchaustegui systematic analysis of West Indian emydids, Miranda, Museo Nacional de Historia Nat- it is not surprising that the taxonomy of this ural, Rep(ublica Dominicana; Edward L. Car- group has remained unstable. Subsequent au- dona and Fred V. Soltero Harrington, De- thors have recognized as many as five species partment ofNatural Resources, Puerto Rico; (Henderson and Schwartz, 1984; Schwartz Colin Higgs and Egbert Wallace, Ministry of and Henderson, 1985; Schwartz and Thom- Agriculture, Fisheries and Local Govern- 1988 SEIDEL: WEST INDIAN EMYDID TURTLES 3 ment, Bahamas; Patrick Fairbairn, Ministry stepwise discriminant analysis (BMDP7M; of Mining and Natural Resource Conserva- Dixon, 1977) and principal components tion Department, Jamaica. For field assis- analysis (PCA) (SPSS-PAL; Kim, 1975). tance, provision of laboratory space, or lo- These multivariate techniques were applied cality information I thank A. Schwartz, R. I. to evaluate overall divergence or homoge- Crombie, D. Alcantara, P. Merejo, S. J. In- neity and test which populations are mor- chaustegui Miranda, Margarita Paul, and phologically distinct. Initially sexes were Loretta Seidel, U. Fritz, J. Davies, W. Sam- treated separately and two discriminant anal- uels, K. Bjorndal, J. P. Ross, R. Ashton, E. yses (male and female) were conducted to Shaw, J. Rivero, L. Wesenauer, R. Calero, F. avoid any influence of sexual dimorphism. Bird Pico, R. Thomas, R. Adamcik, J. Bar- The linearly related effects of size (age) on quet, G. Pregill, J. Pinero, F. Burton, and F. character variation were removed by regres- Fas. For providing specimens of T. scripta I sion analysis which produced 49 residual thank J. B. Iverson, J. W. Gibbons, T. Lamb, characters regressed from carapace length. A M. Goode, and D. Badgley. For loan of mu- second discriminant analysis was conducted seum material I thank P. Alberch, W. Auf- to determine if populations remained mor- fenberg, J. T. Collins, M. Klemens, A. Kluge, phologically distinct when sexes were com- H. Marx, J. Legler, C. J. McCoy, R. W. bined. This analysis utilized seven sets of McDiarmid, J. Mecham, P. Meylan, W. principal components as variables (extracted Palmer, J. P. Rosado, F. L. Rose, A. F. from the original set of 50 characters) to iso- Schwartz, E. E. Williams, G. Zug, and R. G. late that portion of each variable correlated Zweifel. I thank W. Fink and D. Swofford for to size or sex. The taxonomic utility of each assistance with computerized cladistic anal- set of principal components to discriminate ysis. I acknowledge Marshall University for between or among populations was tested by granting me sabbatical leave, and providing multivariate analysis of variance (SAS- computer time and partial funding through MANOVA; Barr et al., 1976). These data were faculty development and research grants. I further analyzed by cluster analysis to illus- also thank Marshall Foundation Inc. for fi- trate morphological affinities in the form of nancial support. I thank J. Dudley and V. hierarchial phenograms. Mahalanobis' dis- Crager for typing, S. Lawton, G. Sutphin, and tances, calculated from discriminant scores,