The loach minnow (Tiaroga cobitis) is a species of freshwater ray-finned fish belonging to the family Leuciscidae, the shiners, daces and minnows. It is the only species in the monospecific genus Tiaroga. It occurs in streams and small rivers throughout the Gila River and San Pedro River systems in Arizona, New Mexico, and Sonora; it is now considered extinct in Mexico. This species have an olivaceous body, highly blotched with darker pigment. They have dirty-white spots before and behind base of dorsal fin, and on lower and upper sides base of caudal. Breeding males have vivid red-orange markings on bases of fins, body, and lower head. Breeding females become yellow on their fin and lower body. A female can contain 150 to 1200 mature ova. Males turn red on their fins and above their mouths when they are ready to breed.
Habitat and food
Loach minnows can be found at turbulent, rocky riffles of mainstream rivers. They prefer moderate to swift current velocity and gravel substrates. Members of this species are opportunistic benthic insectivores: they seek food at the bottom substrate for riffle-dwelling larval ephemeropterans, simuliid, and chironomid dipterans.
Conservation
Loach minnow was proposed (USDI, Fish and Wildlife Service [USFWS] 1985) and subsequently listed (USFWS 1986) The critical habitat designation was subject to controversy and litigation, causing it to be rescinded, redesignated and altered. In 2012, the loach minnow was declared "endangered" alongside the spikedace (Meda fulgida),