Black ratsnake

The back of this snake varies from plain black to pale with dark blotches. A dark stripe extends posterior from the eye, but stops at the mouth line. Light reddish-colored skin between the scales is frequently visible. The belly, especially the anterior half, is light with white and black checkerboard markings. The posterior end of the belly is white with some dark mottling. The chin and throat are white or cream colored. The anal plate is divided and the scales are weakly keeled. (information from "A Field Guide to Oklahoma's Amphibians and Reptiles")