Viper is a poisonous snake, also known as black-spotted viper, with a body length of 0.9 to 1.3 meters. The head is broad triangular, distinct from the neck, and the snout is short and round. The small scales on the back of the head are ribbed, the nostrils are large, and they are located at the upper end of the snout.

The back of the Viper is brownish-gray, with 3 large round spots in longitudinal rows, each round spot The center is purple or dark brown, the periphery is black, and the outermost has irregular dark brown markings. The abdomen is gray-white, with thick dark brown spots scattered on the back, dark brown, with 3 rows of light brown chain-shaped oval spots, the outermost edge of each oval spot is yellow-white, followed by black, and there are irregularities scattered among the 3 rows of spots. small spots. The ventral surface is grayish-white, and each ventral scale has 3 to 5 purple-brown spots, and the front and rear are connected slightly in longitudinal rows.