CUI-UI Chasmistes cujus (Cope, 1883) 



Order: CYPRINIFORMES Family: CATOSTOMIDAE 



Distinguishing characteristics : A large, heavy-bodied sucker, commonly reaches 6 

 pounds in weight, with subterminal mouth, thin non-papillose lips, oblique lower jaw, 

 and fewer than 70 scales in the lateral line . 



Present distribution : Pyramid Lake, Washoe County, Nevada. 



Former distribution : Pyramid and Winnemucca Lakes and the lower part of Truckee 

 River, Nevada. 



Status : Seriously depleted. The relict lake suckers of the genus Chasmistes (3 recognized 

 living species) are either extinct or threatened. This one has the best chance for survival. 

 It is of both economic (to the Indians) and biological importance. 



Fecundity : Not known. Eggs are small and numerous. 



Reasons for decline : Declining flow in lower Truckee River due to dams and irrigation. 



Protective measures already taken : Catch limits have been imposed on non-Indians . 

 Plans have been suggested for spawning habitat restoration. 



Measures proposed : Restoration of spawning access and habitat . Increased effort at 

 artificial propagation and stocking of young in Pyramid Lake and, if possible, in some 

 other suitable lake . 



Number in captivity : None . 



Culture potential in captivity : Has not been reared in captivity beyond the yolk-sac 

 stage. 



Remarks : This is a relict genus with 3 recognized living species inhabiting western 

 lakes . It was more widespread and speciose in the Plio-Pleistocene epochs . Data 

 submitted by Dr. Robert R. Miller, University of Michigan and by the Nevada Fish 

 and Game Department. 



References : 



Johnson, V. K. 1958. Pyramid Lake . Fisheries Management Report . Nevada 



Fish and Game Commission, Dingell Johnson Project FAF-4R, 47 p. , 



17 graphs, 3 maps, 3 tables. 

 La Rivers, I. 1962. Fish and fisheries of Nevada. Nevada State Fish and Game 



Comm. , 782 p . 

 Miller, R. R. 1965. Quaternary freshwater fishes of North America. In press 



in INQUA volume to be distributed in August at Boulder, Colorado. 



, and G. R. Smith. 1967. New fossil fishes from Plio-Pleistocene 



Lake, Idaho. Occ . Pap. Mus . Zool . Univ. Mich., No. 654, 24 p. 

 Snyder, J. O. 1917. The fishes of the Lahontan system of Nevada and northeastern 



California. Bull. U.S. Bur. Fish., 35 (1915-16): 31-86. figs. 1-9, pis. 3-4, 



1 map . 



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