Biogeographica 1998, 74(3): 117-124 HISTOCOMPATIBILITY IN PARTHENOGENETIC LIZARDS OF THE COPHORUS COZUMEL COMPLEX FROM THE YUCATAN PENINSULA OF MEXICO Oswaldo HERNANDEZ-GALLEGOS ,, Nora MANRIQUEZ-MORAN 1-1> Fausto R. MENDEZ 1 , Maricela VJLLAGRAN 2 & Orlando CUELLAR 3 1 Laboratorio de Herpetología, Departamento de Zoología, Instituto de Biología, Universidad Nacional Autónoma de Méico, A.P. 70-173, C.P 04510, México, 20, D.F. MEXICO 2 Laboratorio de Biología de la Reproducción, Facultad de Ciencias, Universidad Nacional Autónoma de Móxico, A.P 70-515, C.P. 04510, México 20 D.F, MEXICO 3 Department of Biology, Uiversit of Utah, Salt Lake City Utah, 84112, and .O. Box 17074, Salt Lak Cit Utah 84117, U.S.A. ASTRCT.- Analysis of skin grafting in parthenogenetic lizards of the Cnemidophorus cozumela complex of the Yucatán Península reveled genetic homogeneity within mainland populations of C. cozumela maslini and between them and C. cozumela cozume/a from Isla Cozumel. Such genetic identicity provides conclusive evidence that ali of these populations originated from a single ancestral female and belong to a single species C. cozumela. The subspecific status of C. cozme/a maslini and the specific status of C mas/ini is therefre nullified. KY-WORS.- Lizards, Cnemidophorus, Parthenogcnesis, Transplantation, Histocompatibility, Yucatán Península RSUME.- L'analyse des grefcs d'épidermc chez les lézrds parthénogénétiques du complexe Cnemidophorus cozumela de la Péninsule du Yucatan, a révélée une homogénéité génétique a l'intérieur des populations continentales de C. cozumela mas/mi et entre ces derniers et C. cozumela cozumela de l 'fe de Cozumel. Une telle identité génétique suggere que ces populations ont comme origine un seul ancetre commun femelle et appartiennent a la seule espece C. cozumela. L statut sous-spécifique de C. cozume/a maslini ainsi que celui d'espece de C. maslini sont par conséquence invalidés. MOTS-CLES.- Lzards, Cnemidophorus, Parthénogenese, Transplantation, Histocompatibililé, Péninsule du Yucatan INTRODUCTION The parthenogenetic lizards of the Yucatán península of Mexico are collectively known as the Cnemidophorus cozumela complex. The complex initially consisted of a single taxon, Cnemidophorus deppei cozumelus (GADOW, 1906). In 1962, McCOY and MASLIN partitioned it into two subspecies, Cnemidophorus cozumelus cozumelus from Isla Cozumel and the states of Campeche and Quintana Roo, and Cnemidophorus cozumelus rodecki fom Isla Mujeres, Isla Contoy and a small segment of the adjacent mainland (Puerto Juárez). In a later taxonomic revision of the complex, FRITS (1969) recognized C. rodecki as a distinct species and divided C. cozumelus cozumelus into two subspecies, C. cozumela cozumela fom isla Cozumel and C. cozumela maslini fom