Its extremely small range, which is restricted to a few rivers in the lowlands of southwestern Quebec, has contracted significantly in the past few decades. Confirmed populations currently exist in the St. Lawrence and Richelieu rivers. Rivière des Mille Îles likely supports a remnant population. The copper redhorse is one of seven species of the genus "Moxostoma" (family Catostomidae) occurring in Canada. Its discovery has been attributed to Vianney Legendre in 1942, but it appears to have been first described by Pierre Fortin in 1866 as an already known species of the genus "Moxostoma".