any of various venomous snakes including the adder and Siberian pit viper; typically characterized by a thick body, thin tail, and a triangular head

Snake Island viper (Gloydius shedaoensis), a venomous snake endemic to Shedao Island in China that feeds on migrating birds

snake island viper (Gloydius shedaoensis); a pit viper endemic to Shedao Island that feeds on migrating birds