The chiselmouth is an unusual cyprinid fish of western North America. It is named for the sharp hard plate on its lower jaw, which is used to scrape rocks for algae. It is the sole member of the monotypic genus Acrocheilus and is a close relative of the Gila western chubs, and is known to hybridise with Ptychocheilus oregonensis.
The desert dace is a rare cyprinid fish known only from the warm springs and creeks of Soldier Meadow in western Humboldt County, Nevada, USA. It is the only member of the monotypic genus Eremichthys. The species is also notable for its ability to live in waters as warm as 38 °C (100 °F). It is the sole member of its genus Eremichthys.
The Borax Lake chub is a rare cyprinid fish found only in outflows and pools around Borax Lake, a small lake of the Alvord basin, Harney County, Oregon.
The Lahontan redside is a cyprinid fish of the Great Basin in eastern California and western Nevada.
The splittail, also called Sacramento splittail, is a cyprinid fish native to the low-elevation waters of the Central Valley in California. It was first described by William O. Ayres in 1854. It is the sole living member of its genus, the Clear Lake splittail P. ciscoides having become extinct in the 1970s.
The Santa Ana sucker is a freshwater ray-finned fish, endemic to California. It is closely related to the mountain sucker and has dark grey upper parts and silvery underparts. It grows to a maximum length of 25 cm (10 in), but most adults are much smaller than this. It feeds on algae, diatoms and detritus on the floor of shallow streams with sand, gravel or cobble bottoms. It is found in only a few streams in southern California, and many of these in the Greater Los Angeles metropolitan area have been restricted to concrete channels. Because of its small area of occupancy and vulnerability, the International Union for Conservation of Nature has rated this fish as "endangered".
The smoothback angelshark is an angelshark of the family Squatinidae found in the eastern Atlantic.
The northern leatherside chub is a cyprinid fish of western North America.
The relict dace is a cyprinid fish of the Great Basin of western North America. It is the sole member of its genus.
The Railroad Valley springfish, Crenichthys nevadae, is a rare goodeid fish of the Great Basin of western United States, occurring naturally in just seven thermal springs of Railroad Valley in Nye County, Nevada.
The White River springfish is a species of fish in the family Goodeidae, the splitfins. It is a rare species of the Great Basin of western United States, where it is endemic to isolated warm springs in the White River drainage of eastern Nevada.
The Virgin spinedace is a cyprinid fish of the Virgin River, a tributary of the Colorado River in the United States.
The Yaqui sucker is a species of ray-finned fish in the family Catostomidae. It is found the Aridoamerica region of northern Mexico and south-western United States. Catostomus bernardini or Yaqui sucker belongs to the family Catostomidae. The Yaqui sucker is related to the Sonora sucker and could possibly be a subspecies of the Gila sucker.
The spikedace is an endangered species of ray-finned fish in the family Cyprinidae. It is found in Arizona and New Mexico in the United States. It lives in fast-moving streams.
The whitefin swellshark is a species of catshark, belonging to the family Scyliorhinidae, endemic to southeastern Australia. It is found 126–554 m (413–1,818 ft) down, on the outer continental shelf and upper continental slope. Reaching 1.1 m (3.6 ft) in length, this shark has a very thick body and a short, broad, flattened head with a large mouth. It is characterized by a dorsal color pattern of dark saddles and blotches over a brown to gray background, and light fin margins. When threatened the whitefin swellshark can inflate itself with water or air to increase its size. Reproduction is oviparous. As of 2019 The International Union for Conservation of Nature (IUCN) has assessed this species as Critically Endangered due to the significant decline of the population.
The zebra mbuna is a species of cichlid endemic to Lake Malawi in Africa. This species can reach a length of 11.3 cm (4.4 in). It feeds on aufwuchs, a surface layer of mostly algal material that grows on rocks. This cichlid is a mouthbrooder and the female broods the eggs in her mouth for about three weeks. This fish can sometimes be found in the aquarium trade.
Garra geba is a species of cyprinid fish in the genus Garra. It is endemic to Ethiopia.
Gobioclinus gobio is a strictly marine ray finned fish, also called Gobioclinus gobio. Its common name is the palehead blenny, and is sometimes referred to as the goggle-eye blenny. It can be identified by its greenish top, red belly, and multicolored banding. L. gobio is a benthic organism with a wide range, taking up residence in a number of coastal environments from Florida to Brazil. This means the fish can live in equatorial, subtropical, and tropical climatic zones. It is native to coastal areas of the Caribbean. Its diet consists mainly of different molluscs and echinoderms.
Percina roanoka, the Roanoke darter, is a species of freshwater ray-finned fish, a darter from the subfamily Etheostomatinae, part of the family Percidae, which also contains the perches, ruffes and pikeperches. It is native to Virginia and North Carolina in the United States and is present in West Virginia, possibly from introduction. It is found in the Roanoke, Tar, and Neuse river systems, typically in small to medium size rivers. It is a colorful species with an average length of 4.3 centimeters (1.7 in). It feeds on insect larvae and other small invertebrates, and spawns in late May and June. It is a common fish with a very wide range and the International Union for Conservation of Nature has classified its conservation status as being of "least concern".
Acanthobunocephalus scruggsi is a species of banjo catfish found in the tributaries of the lower Purus River. Due to gold mining in the region, the species could become more critically endangered and possibly even be driven into extinction.
