The Spotted Sucker lives in eastern and central North America from the lower Great Lakes east to Pennsylvania, south to the Gulf Coast and Florida, and west to Texas. In Ontario, the species has been reported in Lake St. Clair and western Lake Erie as well as the Detroit, St. Clair, Sydenham and Thames rivers. The Spotted Sucker prefers clear lakes, creeks and small rivers with sandy, gravely, or hard-clay bottoms without silt.

The adult body of the Spotted Sucker is rather elongated and somewhat compressed laterally, while it is more cylindrical when young. The average length of Ontario adults is 22 to 28 cm and weight rarely exceeds 1 kg. This species has a small, protrusible, suctorial mouth with no teeth and the pharyngeal teeth are short. The Spotted Sucker has distinctive rows of square, brown-black spots on the base of the exposed portion of each scale that are more conspicuous on sides, forming eight to ten rows along the body beyond the head. The dorsal surface and upper sides are dark olive to brown while the sides of the body are mostly bronze green, coppery or silvery.