Abstract

We compared 786 base pairs of cytochrome b mitochondrial DNA sequence to examine the evolutionary relationships among seven species belonging to three genera of Asian newts: Paramesotriton, Pachytriton, and Cynops. We find strong evidence supporting recognition of a clade for these genera. Although bootstrap support values are relatively low, both parsimony and likelihood analyses suggest that the species of Paramesotriton sampled form a monophyletic group with Paramesotriton caudopunctatus basal to the other three species. Cynops appears to be paraphyletic, with Pachytriton and Paramesotriton being more closely related to Cynops pyrrhogaster than to Cynops cyanurus. Pachytriton and Paramesotriton exhibit some morphological similarities and have more specialized breeding habits and environmental requirements than Cynops, suggesting that they shared an evolutionary history before diverging. Our morphological investigations corroborate previous studies that suggested Cynops is the most generalized representative of the clade and that it retains several ancestral character states.