HUMPBACK CHUB Gila cypha (Miller, 1946) 



Order: CYPRINIFORMES Family: CYPRINIDAE 



Distinguishing characteristics : A strongly compressed Gila with the sides of the body 

 slightly convex and with a prominent abrupt hump over the occiput; body almost entirely 

 devoid of scales (except along lateral line) which have basal radii. Fins expansive, 

 flacate; snout fleshy; mouth inferior; eye very small . 



Present distribution : Green and Colorado Rivers , from Grand Canyon area northward 

 to vicinity of Flaming Gorge Dam on Utah-Wyoming border. 



Former distribution : Unknown . 



Status : Occurs in such small numbers in widely separated places that it is considered 

 as probably in jeopardy. 



Estimated numbers : Unknown . 



Fecundity : Unknown . 



Reasons for decline : Unknown . 



Protective measures already taken : Research studies are now attempting to determine the 

 distribution, abundance, and ecology of this form and to determine its proper taxonomic status. 



Measures proposed : Continuation of the above research studies . 



Number in captivity : None . 



Culture potential in captivity : Unknown . 



Remarks: This fish has been taken in very small numbers from widely separated points in 

 the Green and Colorado Rivers. The original specimens came from the Grand Canyon. Six 

 or seven additional specimens were taken from the Hideout Flat area of the Green River 

 near the Wyoming line (now inundated by Flaming Gorge Dam) . Additional fish have been 

 taken in the Lee's Ferry area of the Colorado River and in the Green River near the 

 confluence of the White and Duchesne Rivers. Data submitted by Dr . D. R. Franklin, Utah 

 Cooperative Fishery Unit, Utah State University. 



References : 



Miller, R. R. 1946. Gila cypha , a remarkable new species of cyprinid fish from 

 the Colorado River in Grand Canyon, Arizona. Jour. Wash. Acad. Sci . , 

 Vol. 36, No. 12, p. 409-415. 



. 1961 .Man and the changing fish fauna of the American Southwest. 

 Pap. Mich. Acad. Sci., Arts, and Letters . 46(1960), p. 365-404. 

 Holden, P. B. 1970. Systematic studies of cyprinid genus Gila in the upper Colorado 

 River Basin. Copeia . No. 3, pp. 409-420. 



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