The light areas on back may be vaguely diamond shaped, but the pattern is best described as consisting of dark brown chainlike markings on a ground color of lighter brown or dirty yellow. Belly yellow, marked with black or dark brown spots or half moons. Adult male: Unique among serpents of our area in having numerous raised protuberances (papillae) under chin. Scales keeled ;anal divided. Similar species: Cottonmouth tends to move slowly and often holds mouth open when approached, and are usually a plain gray or dark brown.