Flannelmouth Suckers are native to the big rivers of the Navajo Nation. They are found within the San Juan, Colorado and Little Colorado Rivers. Suckers have large fleshy lips, which they use to feed on the bottom of the river. Adult Flannelmouth Suckers commonly grow to 20 inches in length. They typically eat aquatic insects and other invertebrates, algae and inorganic material. These fish are adapted to living in large rivers that flood during spring and the summer monsoon period.

Fish are called "Lóó" in the Navajo language. Traditional Navajo People belief that fish are closely related to reptiles and they should not be eaten. It is said that expectant parents should not fish or eat fish.