In animal classification, mud snakes belong to Reptiles, Squamata, Snake suborders, Nasperidae, and water snakes. The body of the mud snake is 0.5~0.7 meters long, the back is khaki yellow, scattered with black dots in vertical rows, the first row of back scales on both sides is black, and the second and third rows are black. The scales are white, the ventral surface is yellow, and the front edge of each ventral scale has a black spot.

The mud snake has a cylindrical body and a short tail. Single internasal scale, tangent to left and right nasal scales, dorsal nostrils, small eyes, 1 preorbital scale, 2 retroorbital scales, 1~2 temporal scales, and 7 (8, 9) upper lip scales in a pattern of 3 -1-3 (4, 5) formula. The dorsal scales are smooth, 23(25)-23(25)-19 rows, the ventral scales are 139~155, the anal scales are divided into two, and the lower caudal scales are 38~51 pairs.