Western pygmy rattlesnake

The ground color of the western pygmy rattlesnake is gray. It has short, wide, mid-dorsal, dark blotches on each side. A male may have a lighter ground color than a female. In most individuals a thin reddish to chestnut mid-dorsal stripe extends through the dorsal blotches. The dorsal scales are keeled and there are nine large scales forming an oval on top of the head between the eyes and nostrils. It has a heat sensitive pit between (but below) the eye and nostril on each side of the face. There is a dark bar on each side of the head from the eye to the back of the corner of the mouth. The pupil is vertical. The head is visibly wider than the neck. The tail is thin and the rattles are small. A neonate may have yellow on the end of the tail. The belly is cream-colored with many dark blotches or bars. There is a single anal plate and a single row of scales under the tail. (information from "A Field Guide to Amphibians and Reptiles of Oklahoma")