Description of a new species of the Asian newt genus Tylototriton (Amphibia, Urodela, Salamandridae) from Hunan Province, China

Abstract

The newt genus Tylototriton is widely distributed in east, southeast, and south Asia. Previous studies have shown that basic surveys of this genus are far from comprehensive, and unknown species still exist within the group. In this study, we described a new species of this genus, Tylototriton gaowangjienensis sp. nov., from Gaowangjie National Nature Reserve in Hunan Province, China, based on evidence from molecular identification and morphological comparisons. Additionally, we conducted phylogenetic analysis of the genus to elucidate the taxonomic status of the new species. Based on combined mitochondrial 16S rRNA and ND2 gene sequences, the phylogenetic tree supported the new species as a member of the T. wenxianensis species subclade in the subgenus Yaotriton. It can be distinguished from its congeners by the combination of the following characteristics: (1) medium-sized body; (2) finger tips extending beyond the snout while forelimbs stretched forward; (3) tips of forelimbs and hindlimbs reaching and overlapping when folded towards the body; (4) snout edge round; (5) absence of small papillae in the male cloacal fissure; (6) dorsal ridges narrow, with width smaller than the eye diameter; (7) head length (HDL) greater than head width (HDW) (HDL/HDW = 1.04~1.22); (8) orange markings absence on the parotoid; (9) nodule-like warts on body sides continuous; (10) vomerine teeth not connected at the tip, extending to the occipital bone at the posterior end.