MOAPA DACE Moapa coriacea (Hubbs and Miller, 1948) 



Order: CYPRINIFORMES Family: CYPRINIDAE 



Distinguishing characteristics: A monotypic genus with 5-4 dentition, hidden pre- 

 maxillary frenum, small (70-80) deeply embedded scales in leathery-textured skin, and 

 a prominent black spot at caudal base . 



Present distribution : Restricted to warm springs and their outlets near source of 

 Moapa (Muddy) River, Clark County, Nevada. 



Former distribution: Not known to be different from present . 



Status : In peril . 



Estimated numbers : 500 to 1,000. 



Fecundity : Unknown . 



Reasons for decline : The springs and headwaters of Moapa River are being altered for 

 various commercial domestic water uses; competition from exotic species; only one 

 population remains completely undisturbed. 



Protective measures already taken : None . 



Measures proposed : Set aside Warm Springs Ranch as a wildlife monument; prevent 

 habitat alteration by man . 



Number in captivity : None . 



Culture potential in captivity : Not likely to reproduce well . 



Remarks: This genus is known only from a very restricted area; it is a biological relict 

 threatened by exotic species (gambusia, bullfrogs) and a proposed irrigation and dam 

 project. Data submitted by Dr. Robert R. Miller, University of Michigan, and Dr. James E, 

 Deacon, Nevada Southern University, Las Vegas. 



References : 



Hubbs , C . L . and R . R . Miller . 1948 . Two new , relict genera of cyprinid fishes 



from Nevada. Occ. Pap. Mus . Zool. Univ. of Mich., No. 507, 30 p . 

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



Commission, 782 p. 

 Minckley, W. L. and J. E. Deacon. 1968. Southwestern fishes and the enigma of 



"endangered fishes." Science 159 (3822) , p . 1424-1432 . 



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