A NEW CRYPTIC SPECIES OF BUSH FROG (AMPHIBIA: ANURA: Raorchestes) FROM THE SOUTHERN EASTERN GHATS, INDIA

Abstract

A new cryptic lineage of bush frogs of the genus Raorchestes from the understudied Eastern Ghats of India is described. Molecular phylogenetic reconstructions using mitochondrial 16S rRNA gene sequences suggest that the new species belongs to the Raorchestes charius clade, is sister to the allopatric R. charius of the Western Ghats and support the species-level distinctiveness of the lineage. The new species morphologically resembles R. charius from which it can be distinguished using the following characters: narrower head (HW/SVL 0.31 vs 0.34–0.36), wider inter upper eyelid (IUE/SVL 0.14–0.16 vs 0.11–0.13), greater maximum upper eyelid width (UEW/SVL 0.10–0.12 vs 0.06–0.09) and shorter thigh (TL/SVL 0.32–0.43 vs 0.44–0.51). Acoustic observations from the breeding males further corroborate the distinct specific status of the new species. The discovery of this new species of bush frog from an understudied landscape suggests that additional extensive surveys in the Eastern Ghats would yield several more amphibian lineages yet unknown to science.