The Mexican tetra, also known as the blind cave fish, blind cave characin, and blind cave tetra, is a freshwater fish of the family Characidae of the order Characiformes. The type species of its genus, it is native to the Nearctic realm, originating in the lower Rio Grande and the Neueces and Pecos Rivers in Texas, as well as the central and eastern parts of Mexico.
The Amblyopsidae are a fish family commonly referred to as cavefish, blindfish, or swampfish. They are small freshwater fish found in the dark environments of caves, springs and swamps in the eastern half of the United States. Like other troglobites, most amblyopsids exhibit adaptations to these dark environments, including the lack of functional eyes and the absence of pigmentation. More than 200 species of cavefishes are known, but only six of these are in the family Amblyopsidae. One of these, Forbesichthys agassizii, spends time both underground and aboveground. A seventh species in this family, Chologaster cornuta, is not a cave-dweller but lives in aboveground swamps.
The golden cave catfish is a critically endangered species of airbreathing catfish. This cavefish is only known to live in the Aigamas cave, Otjozondjupa region, Namibia. It has also been reported from the nearby Dragon's Breath Cave, but this is an error. The golden cave catfish lack pigmentation and are up to 16.1 cm in standard length. They have very small eyes that are covered with skin, and are probably effectively blind. They feed on detritus and invertebrates that fall into the lake in which they live. The population is estimated at 200–400 individuals. Little is known about its reproduction, and attempts to breed it in captivity have failed. The population is threatened by chance events and water extraction from the cave lake, which has resulted in a drop of the water level.
The Alabama cavefish is a critically endangered species of amblyopsid cavefish found only in underground pools in Key Cave, located in northwestern Alabama, United States in the Key Cave National Wildlife Refuge. It was discovered underneath a colony of gray bats in 1967 by researchers Robert A. Kuehne and John E. Cooper and scientifically described in 1974.
The spring cavefish is the only member of the genus Forbesichthys and is one of seven species in the family Amblyopsidae. This species is listed as state endangered in Missouri, but it is considered to be of least concern by the IUCN Red List due to its relatively large population size and number of subpopulations. The spring cavefish inhabits caves, springs, spring runs, and spring seeps. It is subterranean, emerging at dusk and retreating underground an hour or two before dawn. The species is located within areas of the central and southeastern United States. It stays underground after dawn, but then emerges into surface waters at dusk. They are a carnivorous fish and are well adapted to their environment. The species' breeding behavior is rarely documented. Spawning occurs underground and in darkness between January and April. The status and distribution of cave-obligate species is incomplete or lacking entirely, which makes conservation and management decisions difficult. Kentucky and Missouri are the two main states that have their agencies managing this species in some way.
The Somalian blind barb is a ray-finned fish species in the family Cyprinidae. It is the only member of the genus Barbopsis. This troglobitic fish is found only in Somalia.
Labeobarbus somereni, or Someren's barb, is a species of ray-finned fish in the family Cyprinidae. It is found in Burundi, Rwanda, Tanzania, and Uganda. Its natural habitat is rivers. It is not considered a threatened species by the IUCN. Local names for the fish in Rwanda include ikinanga, inkwenwe, ifurwe (Satinsyi) and urwozi (Nyabarongo).
Chelaethiops minutus is a species of ray-finned fish in the family Cyprinidae. It is endemic to Lake Tanganyika and its outflow, the Lukuga River and is found in Burundi, Democratic Republic of the Congo, Tanzania, and Zambia.
Phreatichthys andruzzii, a species of cyprinid fish, is the only species of the genus Phreatichthys, and is endemic to Somalia. This cave-adapted fish is whitish and blind. It has no scales. It is considered to have evolved in the cave environment for some two million years. Its name derives from the Greek words phreasatos for spring, and ichthys for fish. It grows to a maximum length of 6.2 cm (2.4 in).
Typhlogarra widdowsoni or Garra widdowsoni, the Iraq blind barb or Haditha cave garra, is a species of cyprinid fish endemic to underground water systems near Haditha in Iraq. Although traditionally placed in its own genus Typhlogarra, this is not supported by genetic evidence, leading to its move to Garra. This cavefish is considered critically endangered because of water extraction, which has lowered the groundwater level. Once abundant, a survey in 2012 found that it now was very rare. Another species from the same place, Caecocypris basimi, may already be extinct. The only other known cavefish in Iraq is Eidinemacheilus proudlovei.
The Mexican blind brotula is a species of viviparous brotula endemic to Mexico, where it is found in sinkholes and caves. It is known as sak kay in Mayan and dama blanca ciega in Spanish. This cavefish grows to a standard length of 9.7 cm (3.8 in). It is the only known member of its genus.
The blind cave eel is a species of cavefish in the family Synbranchidae. It is the longest cavefish in Australia and one of the only three vertebrates in Australia that is restricted to underground waters, the other being the blind gudgeon and the Barrow cave gudgeon. It is blind, its body is eel-like and elongated, and it has a non-pigmented skin with colours ranging from white to pink.
The blind swamp eel is a species of fish in the family Synbranchidae. It is endemic to Mexico where it lives in cave systems and is known in Spanish as the anguila ciega. The International Union for Conservation of Nature has rated this cavefish as "endangered".
The Thysville Caves are a cave complex in the Democratic Republic of the Congo, located near the town of Mbanza-Ngungu. The cave complex is fed by tributaries of the Lower Congo River, and extends across an area of 750 square kilometers.
Cavefish or cave fish is a generic term for fresh and brackish water fish adapted to life in caves and other underground habitats. Related terms are subterranean fish, troglomorphic fish, troglobitic fish, stygobitic fish, phreatic fish and hypogean fish.
Labeobarbus bynni, the Niger barb, is an African species of cyprinid freshwater fish. It has often been placed in the genus Barbus, but is now usually placed in Labeobarbus. This is a relatively large barb, up to 82 cm (32 in) in total length. It is caught as a food fish, but catches can vary greatly from year to year.
Jae barb or Dja barb,, is a species of cyprinid fish which like other sub-Saharan "barbs" was formerly placed in the genus Barbus, it has now been reallocated to Enteromius.
The Yellow barb is a species of cyprinid fish in the genus Enteromius.
Lamprologus lethops is a species of cichlid fish from areas with fast current in the Congo River in Central Africa, where it is believed to live in depths as great as 160 m (520 ft) or 200 m (660 ft) below the surface. It reaches up to about 12.5 cm (5 in) in standard length, with females being somewhat smaller than males, is all whitish in color (non-pigmented), and essentially blind as adult, as their eyes are covered in a thick layer of skin. This is entirely unique among cichlids and an adaption to the perpetual darkness of its habitat, similar to the adaptions seen in cavefish. The eyes of juveniles are rudimentary and not covered by skin.
The Hoosier cavefish is a subterranean species of blind fish from southern Indiana in the United States. Described in 2014, A. hoosieri was the first new species of amblyopsid cavefish to be discovered in 40 years.
