A New Species of Trimeresurus Lacepede, 1804 (Squamata: Viperidae) from Southwestern China, Vietnam, Thailand and Myanmar

The pit vipers of the genus Trimeresurus Lacepede, 1804 is one of the largest groups of Asian snakes, distributed from India to China and Indonesia. Recent surveys in Jiangcheng and Simao, Yunnan Province, China resulted in a new species previously allocated to T. albolabris. Combining morphological and molecular data, we describe it as Trimeresurus guoi sp. nov. The new species morphologically differs from T. albolabris in the yellow green ventral color; an indistinct ventrolateral line; the absence of a postocular stripe; the firebrickred iris; a dark red stripe on dorsal tail; hemipenes with relatively weak sparse papillae, reaching 23rd subcaudal when unextruded. Molecularly, the new species forms a clearly divergent lineage (BPP 1.00/ UFB 100). Uncorrected pairwise distances of mitochondrial gene Cyt b between the new species and other known species of the subgenus Trimeresurus range from 0.052 (T. albolabris) to 0.071 (T. insularis).

Automated summary

A new species, Trimeresurus guoi, was discovered in Jiangcheng and Simao, Yunnan Province, China, previously allocated to T. albolabris. This new species is morphologically and genetically distinct from other known species of the subgenus Trimeresurus.