Rediscovery of (Blanford, 1878) (Serpentes, Colubridae) in Xizang, China, with comments on its systematic position.

(Blanford, 1878), a rarely encountered species of Asian snake, is characterized by ambiguous systematics and biology. Based on a sole specimen of rediscovered in southeastern Xizang, China, we conduct a detailed morphological examination and description, and investigate the systematic position of this species. Morphologically, the newly collected specimen is closely aligned with specimens previously described. Mitochondrial DNA-based phylogenetic analyses reveal that constitutes an independent evolutionary lineage, forming a clade with (Anderson, 1879), Vogel & Luo, 2011, Boulenger, 1900, and Grismer, Quah, Anuar, Muin, Wood & Nor, 2014. The closest genetic distance between and its congeners was 10.2%. The discovery of in Medog County, China, signifies an eastward expansion of its known geographical distribution.