[1][2] Head much depressed; snout long; loreal region concave; upper labials projecting, angular.

Upper head-shields smooth; nostril latero-superior, pierced between an upper and a lower nasal; a small postnasal wedged in between the two nasals; these three shields more or less distinctly swollen; fronto-nasal single; pre-frontals obtusely keeled; frontal much narrowed posteriorly, grooved longitudinally; four supraoculars, first and fourth smallest, the two principal separated from the supraciliaries by a series of granules; occipital small, broader than the interparietal, with which it is usually in contact; subocular bordering the lip, between the fourth and fifth upper labials; temporal scales small, obtusely keeled; two large supra-temporals bordering the parietal; tympanic shield very large, opercle-like.

Dorsal scales small, as large as laterals or slightly larger; 52 to 64 scales round the middle of the body, ventrals included.

Tail about twice as long as head and body; caudal scales very large.

Brown or greyish above, with small black spots which may form a network on the sides; usually one or two pale longitudinal streaks on each side; lower surfaces white.