Gila cypha Miller, 1946
Humpback chub
Gila cypha
photo by The Native Fish Conservancy

Family:  Leuciscidae (Minnows), subfamily: Laviniinae
Max. size:  38 cm TL (male/unsexed)
Environment:  benthopelagic; freshwater, potamodromous
Distribution:  North America: upper Colorado River drainage in Wyoming, Colorado, Utah and Arizona, USA.
Diagnosis:  Body deep and compressed; caudal peduncle long, extremely slender; fins falcate; caudal fin large, forked; angle along anal fin base continues along upper edge of caudal fin. Large-sized individuals possess large, nearly scaleless hump behind small, depressed head; mouth subterminal, extending to front of small eye; 73-90 scales on lateral line; usually 9 dorsal rays; 10 anal rays; pharyngeal teeth 2,5-4.2. Dark olive-gray above, silver side (Ref. 86798).
Biology:  Inhabits swift, rocky runs and flowing pools. The hump at the back of the head directs fish to maintain position in the swift water (Ref. 86798).
IUCN Red List Status: Endangered (EN); Date assessed: 10 February 2012 (B2ab(v)) Ref. (126983)
Threat to humans:  harmless

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