Generic level taxonomy
Our study provides an opportunity to discuss the taxonomic history of two named, but currently synonymised group level taxa within the genus Hylarana (sensu lato).
Hydrophylax Fitzinger, 1843: We report sequences from the type species of Hydrophylax (H. malabarica from ‘Malabar’ India). Our molecular phylogenetic analysis suggests monophyly of the proposed Hylarana malabarica group (containing H. malabarica and H. gracilis) (Fig. 4), along with morphological support (Figs 5, 6). Hylarana cf. leptoglossa, a species closely related to the H. malabarica group, is shown to have distinct finger and toe tips demonstrating that digit tip morphology may not be taxonomically significant for delineating putative generic level taxa like Hydrophylax, as previously suggested (Dubois, 1992). Further morphological and molecular evidence incorporating more samples from the H. malabarica group, as well as closely related members like ‘Hylarana leptoglossa’ and Amnirana would be required to completely resolve the taxonomic status of Hydrophylax. For detailed taxonomic history see generic level taxonomy in the appendix.
Sylvirana Dubois, 1992: Our study does not provide conclusive evidence to address the generic status of Sylvirana, but suggests an interesting biogeographical pattern to understand the dispersal of members of the genus Hylarana. The well-supported sister relationship between the Hylarana malabarica group and H. cf. leptoglossa, a species which was previously regarded as Sylvirana leptoglossa (Dubois, 1992; Frost et al. 2006), indicates that if Sylvirana is considered as a genus, it would include members from throughout much of India and Sri Lanka, as well as Southeast Asia, thus partially supporting the assertions of some studies (e.g. Dubois, 1992, 2005; Frost et al., 2006; Fei et al., 2010). However, this mixed clade is a sequential sister group to the well-supported and phylogenetically distinct Western Ghats-Sri Lankan endemic radiation (H. aurantiaca, H. flavescens and H. temporalis groups). The phylogenetic position of this clade relative to its sister congeners, suggests that the Western Ghats-Sri Lankan endemic radiation came into being through an India-Sri Lanka dispersal event from Southeast Asia through Northeast India.