MODOC SUCKER Catostomus microps (Rutter, 1908) 



Order: CYPRINIFORMES Family: CATOSTOMIDAE 



Distinguishing characteristics : A small, dusky sucker with orange fins; D. 10 or 11, 

 the fin rounded; 73-91 scales in lateral line; eye small; posterior fontanelle of skull 

 of adult very narrow to closed. 



Present distribution : Found in Rush Creek, a small tributary to Ash Creek, and in 

 Ash Creek, near Adin, Modoc County, California; in the Pit River drainage of the 

 Sacramento River basin . 



Former distribution : Not known to be different from present distribution. 



Status: Scarce but more fish found and distributed more widely than previously realized. 

 Collected (May 10, 1968) by California Department of Fish and Game to determine whether 

 the species still survives (it had been reported to be extinct). Its survival not threatened. 

 Habitat reasonably secured and recent observations indicate wider distribution than 

 formerly known (pers . comm. L. Fisk) . 



Estimated numbers : Fair numbers . 



Fecundity : Unknown . 



Reasons for decline : No definite data on former decline, but probably habitat alteration. 



Protective measures already taken : Fully protected under California Fish and Game 

 code. Portions of known habitat on Forest Service land. 



Measures proposed : Set aside a section of Rush Creek as a natural area . 



Number in captivity : None . 



Breeding potential in captivity : Unknown . 



Remarks: This species is believed to be a disjunct, southern relict related to the 

 longnose sucker, Catostomus catostomus . It is sympatric with the Sacramento sucker, 

 Catostomus occidentalis (J. K. Winther, pers. comm., 1967). Data provided by 

 Dr. Robert R. Miller, University of Michigan, Ann Arbor. Collected in Rush Creek 

 in 1969, 1970 and 1971. Discovered in Ash Creek in 1971. 



Reference : 



Fisk, L. 1972. Status of certain depleted inland fishes . California Department of 



Fish and Game, Inland Fish Admin. Dept. , No. 72-1: 13 p. 

 Rutter, C. 1908. The fishes of the Sacramento/San Joaquin basin, with a 



study of their distribution and variation. Bull. U.S. Bur. Fish., 27 (1907): 



103-152, figs. 1-4, pi. 6. 



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