The highfin carpsucker is distinguished by the length of the first ray of its dorsal fin, which reaches to or beyond the back of the dorsal fin. The highfin carpsucker is also a more slender, but deeper-bodied fish.
The river carpsucker has a silvery, deep, rather thick body, a long, sickle-shaped dorsal fin, and whitish lower fins. The center of the lower lip has a nipple-like projection.
The quillback has a deep, rather thick body, with a large snout and a long, sickle-shaped dorsal fin. Unlike the river and highfin carpsuckers, the quillback lacks a nipple-like extension on the lower lip.