The average length of this snake is 0.6 meters. Head large, flattened, quite distinct from neck. Snout broad, short. Eye size moderate, pupils vertically elliptical. Nostrils slit-like. Body stout, strongly flattened along side of back, abruptly tapering tail; skin soft and loose. Crown covered by small scales. A narrow whitish line runs from above eye to angle of mouth; scattered dark flecks on top of head. Dorsal base color light tan to khaki, with a series of 20 to 25 small black lateral spots each surrounded partly or completely by group of smaller cream spots. Young snakes have series of about 30 darker brown dorsal crossbands. All markings are more distinct toward the rear. Base of tail has distinct crossbands, tips unmarked, yellowish.
Rostral scale much broader than high, crescent-like, deeply concave, surmounted on sides by a butterfly’s wing-like, free edged, broad scale; circumocular scales; supralabials, forming cirrated dorsal lip, separated from eye by three rows of scales, about twice as large as those of the ocular ring; 23-29 scales at midbody, arranged in straight regular rings; ventrals 140-145, with lateral keels; anal scale single.
Dorsum light reddish brown to khaki, with a series of small, dark brown lateral spots, each surrounded in its upper half by light dots. A thin light line from eye to angle of mouth. Base of tail with brown cross bands. Ventrum white. Snout-vent length 645-660 mm, tail length 63-72 mm.