Phylogeny of the Mexican coastal leopard frogs of the Rana berlandieri group based on mtDNA sequences.

Phylogenetic relationships among specimens from 25 different locations for the six Mexican coastal leopard frog species of the Rana berlandieri species group were investigated using 797 bp of the mitochondrial 12S rDNA gene. Relationships among the haplotypes obtained were recovered using maximum parsimony and Bayesian analyses. Most of the clades recovered by both tree building methods are strongly supported, but conflicting clades recovered by each analysis are generally poorly supported. Both analyses reject the previously proposed subgroupings of the R. berlandieri species group. Based on the strongly supported relationships, genetic differentiation, and geographic distribution of the haplotypes examined, nine independent lineages appear to comprise the group of study. However, confirmation of the new proposed lineages will require further analyses based on other genetic markers and additional samples that cover their entire geographic distribution. Concordance was noted between Miocene-Pliocene geological and climatic events in Mexico and the relationships recovered among the lineages proposed and their geographic distribution.