Catostomus latipinnis (flannelmouth sucker) is a North American fish identified by its enlarged lower lips. It belongs to the genus Catostomus, commonly known as suckers. Historically, the flannelmouth sucker ranged in the Colorado River Basin, including parts of Wyoming, Utah, Colorado, New Mexico, Nevada, California, and Arizona; however, this species has been entirely extirpated from the Gila River Basin in Arizona.