Phylogeny, taxonomy, and biogeography of the oriental pitvipers of the genus Trimeresurus (Reptilia : Viperidae : Crotalinae): A molecular perspective

Based on sequence variation in 806 bp of the mitochondrial 12S rRNA gene, p hylogenetic relationships were inferred for 14 species of Trimeresurus (sen su late) including all East Asian members. Samples analyzed also included r epresentatives of all assemblages of species that are frequently treated as separate genera except for T. mangshanensis, a type species of the recentl y described monotypic genus Ermia. Results support some previous accounts c hiefly from morphological studies, such as distinct divergence of T. wagler i from the remainder, and monophyly of T. mucrosquamatus, T. flavoviridis, T. jerdonii, T. elegans and T. tokarensis. On the other hand, our results n egated a putative close affinity of T. monticola and T. okinavensis, and in dicated the sister relationship of the latter with T. gracilis. Phylogeneti c relationships revealed in this study suggested that the genus Trimeresuru s dispersed into the Ryukyu region at least three times, and that T. flavov iridis and T. tokarensis from the central Ryukyus constitute a relict clade .