This species of lizard has a large head that is elongated and depressed, with the cheeks swollen in adult males. The snout is longer than the diameter of the orbit (eye cavity). The upper head scales are unequal and smooth or obtusely keeled, the scales being larger on the sinciput (brow) than on the occiput. The "canthus rostralis" and supraciliary (brow) has a clear and sharp edge, two small separated spines or groups of spines above the ear are present or absent; the diameter of the tympanum is half or a little more than half that of the orbit; it has 10 to 13 upper and as many lower labial scales. The body is slightly flattened; dorsal scales are small, uniform, smooth, or feebly keeled in the adult, and strongly keeled in the young, all pointing backwards and upwards; the dorsal crest is reduced to a ridge of enlarged scales; ventral scales are as large as the dorsals, and smooth (keeled in the young); from 115 to 150 scales occur around the middle of the body; the gular (under chin) scales are a little smaller than the ventral (underside) scales; four or five enlarged scales occur on the chin parallel with the anterior labials, separated from them by two rows of scales; a strong transverse fold covered with small scales is seen across the throat; the nuchal and dorsal crests are merely tooth-like protrusions. The legs are strong, covered with uniform, keeled scales; the hind limb when extended forward in a specimen reaches the ear or the rear end of the eye, and further forward in younger individuals. The tail is slightly flattened and covered with keeled scales, which are larger below than above. In the adult male, it is distinctly swollen at the base, the scales on that part of it are thickened, and those of the upper median row are enlarged.