Multilocus Molecular Phylogeny and Morphological Comparisons Provide New Insights into Systematics of the Genus Trachischium Günther, 1858 (Serpentes: Natricidae)

Snakes of the natricid genus Trachischium Günther, 1858 are distributed in the southern Himalayas. Due to their secretive nature and fossorial habits, their taxonomy, evolution, and ecology remain poorly understood. Based on a multilocus molecular phylogeny and morphological comparisons we explored Trachischium systematics. Results indicated that all representatives of Trachischium form a strongly supported clade with their close relatives in Blythia, and that Blythia is nested within Trachischium. Therefore, we suggest that Blythia is synonymous with Trachischium. Molecular data and morphological comparisons revealed cryptic diversity within Trachischium, and thus we describe one new species from China while also excluding T. guentheri and T. tenuiceps from the Chinese fauna.