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.
Typhlonarke is a genus of sleeper ray in the family Narkidae, containing two poorly known species. The group is known for producing electric shocks for defense. Both species are deep-sea rays endemic to the waters off New Zealand. They are not to be confused with the blind electric rays of the genus Benthobatis.
The Blind cave loach is a species of troglobitic stone loach endemic to Thailand. It is only known from one subterranean stream in the Sai Yok Noi cave, which also is inhabited by Pterocryptis buccata. The blind cave loach has no eyes and lacks pigmentation. It grows to 6.8 cm (2.7 in) SL. Despite its common name, there are several other species of blind cave-living loaches.
Prietella is a small genus of North American freshwater catfishes found in Mexico and Texas, and restricted to underground waters.
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".
Typhlichthys subterraneus, the southern cavefish, is a species of cavefish in the family Amblyopsidae endemic to karst regions of the eastern United States.
Leucopatus is a genus of velvet worm in the family Peripatopsidae, containing a single species, the blind velvet worm. It is found in northeast Tasmania, Australia, and is ovoviviparous.
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.
Phreatobius sanguijuela is a South American species of heptapterid catfish that lives in underground waters.
Polycheles typhlops is a species of blind, deep water decapod crustacean with a cosmopolitan distribution. It is "one of the dominant and most characteristic crustaceans in deep-sea communities of the Mediterranean Sea".
Nemacheilus singhi is a species of ray-finned fish in the stone loach genus Nemacheilus, although some authorities place it in the genus Schistura. This species has only been recorded from a single locality in Nagaland, India.
Nemacheilus subfusca is a species of ray-finned fish from the family Nemacheilidae in the genus Nemacheilus which is found in Assam and China. It inhabits pebbly streams. N. subfusca was synonymised with Neomacheilus scaturigina which was described by Menon from the collection of Hamilton. It was, however, then treated as a valid species and sometimes placed in the genus Schistura.
Megalophthalma is an extinct genus of temnospondyl amphibian belonging to the family Plagiosauridae. It is represented by the single type species Megalophthalma ockerti from the Middle Triassic Erfurt Formation in southern Germany, which is itself based on a single partial skull and a fragment of the lower jaw. Megalophthalma is distinguished from other temnospondyls by its very large orbits or eye sockets, which occupy most of the skull and are bordered by thin struts of bone. Like those of most plagiosaurids, the skull flat, wide, and roughly triangular. The orbits are pentagon-shaped. The bones at the back of the skull are highly modified and show similarities with those of the plagiosaurid Plagiosternum. Both Megalophthalma and Plagiosternum lack prefrontal and postfrontal bones. In fact, Megalophthalma and Plagiosternum are thought to form their own clade or evolutionary grouping within Plagiosauridae called Plagiosterninae. In overall form Megalophthalma and Plagiosternum are intermediate between the basal plagiosaurid Plagiosuchus and the derived Gerrothorax.
