Protobothrops xiangchengensis

Protobothrops xiangchengensis, the Szechwan or Kham Plateau pit viper, also called the Sichuan lancehead, is a pit viper endemic to the Hengduan Mountains of south-central China, in Yunnan and western Sichuan. No subspecies are recognised. (The Reptile Database; Wikipedia, general species account)

It has about 25 dorsal scale rows at midbody, 175–194 ventral scales and 7–8 supralabials. The type locality is Xiangcheng in Sichuan, at about 3,100 m. (Wikipedia, general species account)