Roundtail Chub (Gila robusta) is a medium-sized (up to 43 cm) fish that occurs from Wyoming to northwestern Mexico. In New Mexico they occur in the San Juan and Gila river basins. They live in pools and rapids of creeks and small to large rivers and can also be found in large reservoirs. They are opportunistic feeders that eat a variety of invertebrates, fish, and algae. Recent taxonomic work suggests that Roundtail Chub in New Mexico may be the same species as two other limited-distribution fishes of the Lower Colorado River drainage, Gila Chub (Gila intermedia) and Headwater Chub (Gila nigra).