Nerodia clarkii, commonly known as the salt marsh snake, is a species of semiaquatic, nonvenomous, colubrid snake found in the southeastern United States, in the brackish salt marshes along the Gulf of Mexico from Florida to Texas, with a population in northern Cuba.
Populations of the Gulf salt marsh snake (Nerodia clarkii clarkii) from the vicinity of Corpus Christi, Texas, to the Gulf Hammock region of Florida are gray, tan or yellow with four brown to black longitudinal stripes.