Global Range: Widespread throughout lowlands of Atlantic and Gulf slopes (north to Long Island, New York; west to eastern Texas), Mississippi Valley, and north in the Mississippi River basin and Great Lakes drainages to Michigan Lower Peninsula, Wisconsin, and southern Minnesota. Disjunct populations occur in Lake Erie and Lake Ontario drainages, western New York. Rare and localized in the north; generally common elsewhere. Subspecies SAYANUS: Atlantic Slope south to the Satilla River. Subspecies GIBBOSUS: Gulf Slope west of the Mississippi River, Mississippi Valley, and Great Lakes. Intergrades occur from the Saint Marys River of the Atlantic Slope west to the Pearl River of the Gulf Slope (Boltz and Stauffer 1993).