Nerodia

Nerodia is a genus of largely aquatic, nonvenomous snakes, family Colubridae, commonly known as water snakes, comprising nine species, five of which have recognized subspecies. The genus is widely distributed across the southern and eastern United States, extending north into Canada and south into Mexico and Cuba, and is notably absent from the western United States, though two species have become invasive there. Members are relatively heavy bodied, sometimes growing to 1.2 meters or longer, with flattened heads, small eyes with round pupils, and keeled dorsal scales; coloration varies by species and includes banded, blotched or diamond-shaped patterns in browns, olive greens and blacks with yellow or cream accents. The genus feeds primarily on fish and amphibians; well known species include the common water snake, Nerodia sipedon, the diamondback water snake, Nerodia rhombifer, the plainbelly water snake, Nerodia erythrogaster, and the banded water snake, Nerodia fasciata.