PAHRANAGAT BONYTAIL Gila robusta jordani 



Order: CYPRINIFORMES Family: CYPRINIDAE 



Distinguishing characteristics : Similar to Gila robusta robusta but differs by being 

 less elongate, having more scales above, below and on the lateral line and in coloration. 



Present distribution : Outflow of Crystal and Ash Spring, Pahranagat Valley, 

 Lincoln County, Nevada. 



Former distribution : Throughout most of the streams in Pahranagat Valley . 



Status : In jeopardy because of extreme localization. 



Estimated numbers : Unknown . 



Breeding rate in the wild : Unknown . 



Reasons for decline: Irrigation development and establishment of competitive and 

 predatory exotic species throughout the range of this species . 



Protective measures already taken : None . 



Measures proposed : Transplant the species into suitable habitat. 



Number in captivity : None . 



Breeding potential in captivity : Probably poor . 



Remarks : Collecting trips to Pahranagat Valley in 1967 and 1968 resulted in locating 

 very few of these fishes. La Rivers (1962) saw the species at Crystal Spring in 1948-49. 

 Tanner (1950) designated Crystal Spring the type locality. The fish currently appears 

 to be restricted to a small population living in a short section of stream above a main 

 irrigation ditch which accepts the combined outflow from Crystal and Ash Springs. It 

 has not been seen or taken in the outflow from Crystal Spring above the confluence with 

 Ash Spring waters. Submitted by Dr. James E. Deacon, Nevada Southern University, 

 Las Vegas, Nevada, September 8, 1968. 



Reference : 



Deacon, J. E. Unpublished data . 



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