GENETIC-VARIATION, SPECIES STATUS, AND PHYLOGENETIC-RELATIONSHIPS IN ROSE-BELLIED LIZARDS (VARIABILIS GROUP) OF THE GENUS SCELOPORUS (SQUAMATA, PHRYNOSOMATIDAE)

We investigated species boundaries and phylogenetic relationships in t he Sceloporus variabilis group, using multilocus isozyme characters. F orty-one genetic markers were screened in a sample of 238 lizards from 47 localities, representing eight ingroup species. Thirty-four loci w ere variable within or between taxa, Morphologically well-defined spec ies (S. chrysostictus, S., cozumelae, and S. parvus) were strongly and unambiguously differentiated genetically. Within S. variabilis, S. v. maramoralus, high-elevation populations of S. v. variabilis (from Hida lgo, Queretaro and San Luis Potosi), low-elevation populations of S., v. variabilis, and S. v. olloporus, were each recognized as full speci es. Low-elevation populations of S. v. variabilis were only slightly d ivergent from S. v. teapensis and were retained as conspecific, Two di fferent methods of parsimony analysis recovered trees with the followi ng structure: (S., parvus (S. chrysostictus (S., cozumelae + S. variab ilis species-group))), A FREQPARS analysis recovered a different topol ogy.