The river redhorse (Moxostoma carinatum) is a species of freshwater fish endemic to the eastern half of the United States and southeastern Canada.

However, this fish appears to no longer exist in the Châteauguay and Yamaska watersheds and has declined dramatically in the St. Lawrence River.

Due to its narrow range of habitat preferences, spawning requirements and intolerance of high turbidity, siltation and pollution, the river redhorse is susceptible to a number of threats.

Agricultural and municipal activities that affect water quality (increased sediment load, excessive nutrients) also adversely impact this species.

The river redhorse can be distinguished, although with difficulty, from most other members of the genus by its heavy pharyngeal arch with molariform teeth.