Classification / Names
Common names | Synonyms | Catalog of Fishes (gen., sp.) | ITIS | CoL | WoRMS | Cloffa
Actinopterygii (ray-finned fishes) > Cypriniformes
(Carps) > Cyprinidae
(Minnows or carps) > Leuciscinae
Etymology: Couesius: From the American ornithologist Eliot Coues of the US Army Medical Coprs (Ref. 45335).
Environment / Climate / Range
Freshwater; demersal; pH range: 6.5 - 7.8. Temperate; 4°C - 25°C (Ref. 12468); 66°N - 40°N
Length at first maturity / Size / Weight / Age
Maturity: Lm 8.6  range ? - ? cm
Max length : 23.0 cm TL male/unsexed; (Ref. 5723); common length : 10.5 cm TL male/unsexed; (Ref. 12193); max. reported age: 5 years (Ref. 12193)
soft rays: 7 - 9;
Vertebrae: 39 - 44. Distinguished by the spineless fins, normal jaws, and tiny barbel at the corner of the mouth (Ref. 27547). Gill rakers short (Ref. 27547). Caudal moderately forked, with rounded lobes (Ref. 27547). Brown to greenish above, silvery below; a rather indistinct dark or lead-colored band is present along the sides, often extending forward onto the head of small specimens; lower sides and belly often have fine dots of dark pigment (Ref. 27547). In some populations, breeding males develop bright orange-red patches on sides of head and at bases of pectoral fins, but the presence of this color varies from place to place (Ref. 27547).
North America: Alaska (Yukon River drainage). Throughout most of Canada and northern USA; south to Delaware River in New York, south end of Lake Michigan, Illinois, Platte River system in Colorado, and Columbia River drainage in Washington, USA. Relict population in Mississippi River basin in Iowa, USA. Sometimes hybridizes with Rhinichthys cataractae in Lake Superior (Ref. 4564).
Inhabits virtually any body of water, standing or flowing, large or small (Ref. 5723). Most common in gravel-bottom pools and runs of streams and along rocky lake margins (Ref. 5723). Mostly in shallow water, but may move to deeper parts of lakes during hot weather (Ref. 27547). Feeds on zooplankton, algae, terrestrial and aquatic insects, and small fishes (Ref. 1998).
Spawning individuals form schools that move from lakes or deeper parts of streams to shallower water (Ref. 27547). Also Ref. 10280.
Page, L.M. and B.M. Burr, 1991. A field guide to freshwater fishes of North America north of Mexico. Houghton Mifflin Company, Boston. 432 p. (Ref. 5723)
IUCN Red List Status (Ref. 96402)
CITES (Ref. 94142)
Threat to humans
Aquarium: public aquariums; bait: occasionally
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingMass conversion
Estimates of some properties based on models
Phylogenetic diversity index (Ref. 82805
= 1.0000 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.00759 (0.00464 - 0.01241), b=3.09 (2.95 - 3.23), based on LWR estimates for species & Subfamily-body shape (Ref. 93245
Trophic Level (Ref. 69278
): 3.4 ±0.43 se; Based on food items.
Resilience (Ref. 69278
): Medium, minimum population doubling time 1.4 - 4.4 years (tm=2-4; tmax=5; K=0.36).
Vulnerability (Ref. 59153
): Low to moderate vulnerability (31 of 100) .