Cool Geckos: Does Plesiomorphy Explain Morphological Similarities between Geckos from the Southern Cone?
Society for the Study of Amphibians and Reptiles
Journal of Herpetology
The South American genus Homonota comprises 10 species of Broad-Headed Geckos that reach the austral limit for the Gekkota. Historically, morphological data have supported the monophyly of a group including Homonota and the Chilean genus Garthia, with the latter possibly embedded within the former. In contrast, molecular evidence indicates these two genera to be in separate clades and that Homonota is more closely related to the Leaf-Toed Geckos of the genus Phyllodactylus. Here, we analyze 592 morphological characters in Garthia, Homonota, and additional phyllodactylid geckos to evaluate their morphological similarities. Our results indicate that Homonota and Garthia share a great majority of both external and internal characters and are nearly indistinguishable on morphological grounds. These results are interpreted in the light of a recently published multigene molecular phylogeny, and they suggest the symplesiomorphic retention of many morphological states linked to miniaturization and terrestriality in Garthia and Homonota, and concomitant differentiation of the American Leaf-Toed Geckos.