The pit viper is a reptile belonging to the family Viperidae in the order Serpentes. The body length of the pit viper is 60-70 centimeters, and its head is slightly triangular; The back is gray brown to brown, with a dark "∧" - shaped spot on the head and back, and the belly is gray white to gray brown with black spots. The pit viper, when touched, will flip over, and when bitten, people will also flip over, hence its name. The pit viper is distributed in China except for Guangdong, Hainan, and Guangxi. It often inhabits plains, hills, low mountainous areas, fields, streams, and ditches with scattered rocks or grass, and bends into a disc or wave shape. The reproduction, feeding, and activity of pit vipers are all constrained by temperature.

The Japanese pit viper (Gloydius blomhofii) is a venomous snake species belonging to the subfamily Viperinae of the family Viperidae, found in Japan. Unique species of Japan. In Japan, it is commonly referred to as "pit viper".