The rostral scale is broader than it is deep and the inter-nasals are much shorter than the pre-frontals. The frontal is nearly as long as its distance from the end of the snout, which is shorter than the parietal scales. The loreal is square or deeper than it is long. There is one pre-ocular scale, extending to the upper surface of the head, and two or three post-oculars. The temporal scales are very small and numerous. There are eight to eleven upper lip scales, with the third, fourth and fifth, or the fourth fifth and sixth entering the eye. There are three or four lower lip scales, in contact with the anterior chin shields, which are about as long as the posterior. The ventral scales are 259 to 270, the anal entire and the subcaudal 106 to 131.
The body is compressed, with the scales in 25 or 27 rows, disposed obliquely, and the vertebral row is feebly enlarged. It is brown above, with more or less regular angular black crossbars, with or without white spots between them. There is a black band from the frontal shield to the nape and another on each side behind the eye. The lower parts are white, uniform or spotted with brown. The total length is four feet and ten inches (254 mm) , and the tail is one foot long.