Gila nigrescens (Girard, 1856)
Chihuahua chub
Gila nigrescens
photo by Gratwicke, B.

Family:  Leuciscidae (Minnows), subfamily: Laviniinae
Max. size:  24 cm TL (male/unsexed)
Environment:  benthopelagic; freshwater
Distribution:  North America: Mimbres River in New Mexico, USA; Lagunas Guzman and Bustillos, Chihuahua in Mexico.
Diagnosis:  Dorsal soft rays (total): 9-9; Anal soft rays: 8-8. Gila nigrescens can be distinguished by the following characters: lateral line with 67-78 scales; dorsal fin with 9 rays; anal fin with 8 rays; 1st gill arch with 9014 rakers; pharyngeal teeth 2,5-4,2; deep, compressed body; long, fairly slender caudal peduncle; terminal mouth on rounded snout; olive-gray above; silver side; clear to slate gray fins; and breeding individuals with red-orange mouth and paired and anal-fin bases (Ref. 86798).
Biology:  Inhabits flowing pools of creeks and small rivers, usually near brush or other cover (Ref. 86798).
IUCN Red List Status: Vulnerable (VU); Date assessed: 28 February 2019 (B1ab(i,ii,iii,v)+2ab(i,ii,iii,v)) Ref. (126983)
Threat to humans:  harmless

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