|Catostomus latipinnis (central) with Pantosteus jordani above it and Catostomus griseus below. From US National Museum bulletin 47|
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.
The flannelmouth sucker's body is long, starting with a thick anterior that moves down to a thin posterior; respectively, this causes the head to be relatively short and thick. The lower lips are noticeably bulky, with thick and fleshy lobes. In addition, the flannelmouth sucker has large fins, but relatively small scales. Young fish are usually silvery-colored all over, but adults have a typical light gray or tan coloration (often with a lighter underside). Strangely, no bright colors have been found in populations of this species in Arizona, but are found in those from the Colorado basin. Adult fish can also grow to a length of 26 inches and weigh about 8 pounds. It is one of the largest of all suckers.
The flannelmouth sucker can be found in parts of Wyoming, Utah, Colorado, New Mexico, Nevada, California, and Arizona. In Arizona, this species is found in the Colorado River and its larger tributaries. In the mid 1970s, the Arizona Game and Fish Department introduced the fish below the Davis Dam, and the population still persists today. It is extinct in California although strays from the reintroduced Nevada population are occasionally caught in the Californian Colorado River.
While flannelmouth suckers are restricted to larger rivers, its larvae tend to live in shallow areas. Larvae also like deeper water when they are not feeding. In addition, adult suckers prefer great amounts of cover and shade during the daytime.
This species is known to eat inorganic material, planktonic organisms such as copepods, filamentous algae and other macroinvertebrates; this was discovered by examining the stomach contents of flannelmouth sucker larvae.
Breeding season for the flannelmouth sucker occurs in the months of March through July. In Arizona, the fish tend to "run" upstream specifically to spawn, and then immediately leave towards the mainstream. Fins of both sexes often become orange during reproduction.
The flannelmouth sucker is an unprotected species—although not entirely endangered, the species faces many threats. These threats include alterations of river habitats (thermal and hydrologic) caused by hydroelectric dams; blockage of migration; and predation by introduced organisms. In Arizona, the Grand Canyon Protection Act of 1992 reduced the random fluctuation of water releases from the nearby dam in Glen Canyon, and is still enforced today.
- NatureServe 2013. Catostomus latipinnis. The IUCN Red List of Threatened Species. Version 2014.2. Downloaded on 14 September 2014.
- Minckley, W. L. (1973). Fishes of Arizona. Arizona Game and Fish Department. pp. 145-146, 156-157.
- Riley, L. (1995). Personal communication, inter-office memo to B. Spicer. Arizona Game and Fish Department.
- "Flannelmouth sucker". California Fish Website. University of California, Division of Agriculture and Natural Resources. 2017. Retrieved 20 August 2017.
- Clarkson, R. W.; Robinson, A. T. (1993). "Little Colorado River native fishes". Glen Canyon Environmental Studies Phase II 1992 Annual Report. Arizona Game and Fish Department. Prepared for the Bureau of Reclamation, Upper Colorado Region, Glen Canyon Environmental Studies, Flagstaff, AZ. Cooperative Agreement No. 9-FC-40- 07940.
- Sublette, J. E.; Hatch, M. D.; Sublette, M. (1990). The Fishes of New Mexico. University of New Mexico Press, Albuquerque. pp. 202-204.
- Chart, T. E. and E. P. Bergersen. (1992). Impact of mainstream impoundment on the distribution and movements of the resident flannelmouth sucker (Catostomidae: Catostomus latipinnis) population in the White River, Colorado. The Southwestern Naturalist 37: 9-15.