Multilocus phylogeny reveals unexpected diversification patterns in Asian Wolf Snakes (genus Lycodon)

Siler, C. D., C. H. Oliveros, A. Santanen & R. M. Brown. 2013
Zoologica Scripta.

The diverse group of Asian wolf snakes of the genus Lycodon represents one of many poorly understood radiations of advanced snakes in the superfamily Colubroidea. Outside of three species having previously been represented in higher-level phylogenetic analyses, nothing is known of the relationships among species in this unique, moderately diverse, group. The genus occurs widely from central to Southeast Asia, and contains both widespread species to forms that are endemic to small islands. One-third of the diversity is found in the Philippine archipelago. Both morphological similarity and highly variable diagnostic characters have contributed to confusion over species-level diversity. Additionally, the placement of the genus among genera in the subfamily Colubrinae remains uncertain, although previous studies have supported a close relationship with the genus Dinodon. In this study, we provide the first estimate of phylogenetic relationships within the genus Lycodon using a new multilocus data set. We provide statistical tests of monophyly based on biogeographic, morphological and taxonomic hypotheses. With few exceptions, we are able to reject many of these hypotheses, indicating a need for taxonomic revisions and a reconsideration of the group’s biogeography. Mapping of color patterns on our preferred phylogenetic tree suggests that banded and blotched types have evolved on multiple occasions in the history of the genus, whereas the solid-color (and possibly speckled) morphotype color patterns evolved only once. Our results reveal that the colubrid genus Dinodon is nested within Lycodon—a clear finding that necessitates the placing of the former genus in synonymy with the latter.