East central United States and coastal Mexico; from southeastern Iowa at the northern border, to the Yucatan Peninsula at the south, and west Texas at the western border, to central Alabama on the east.
A common snake within its range, this species lives near slow-moving bodies of freshwater. It will often drape itself from branches overhanging the water's edge.
A medium to large semi-aquatic species with rough, keeled scales that averages 30-50 inches in length, but can grow a bit longer. They have a triangular head with large eyes angled slightly upward. Their background color is usually dark olive green to brown with a black net-like pattern down its back connecting to black bars on its sides. The ventral scales are yellow or light brown with black splotches. Adult males have papillae (tiny bumps) on the surface of their chin, which is unique to this species.
Learn more with Schechter Natural History's Guide to Reptiles and Amphibians