Amphibians are ectothermic, anamniotic, four-limbed vertebrate animals that constitute the class Amphibia. In its broadest sense, it is a paraphyletic group encompassing all tetrapods, excluding the amniotes. All extant (living) amphibians belong to the monophyletic subclass Lissamphibia, with three living orders: Anura (frogs), Urodela (salamanders), and Gymnophiona (caecilians). Evolved to be mostly semiaquatic, amphibians have adapted to inhabit a wide variety of habitats, with most species living in freshwater, wetland or terrestrial ecosystems. Their life cycle typically starts out as aquatic larvae with gills known as tadpoles, but some species have developed behavioural adaptations to bypass this.
Caecilians are a group of limbless, vermiform (worm-shaped) or serpentine (snake-shaped) amphibians with small or sometimes nonexistent eyes. They mostly live hidden in soil or in streambeds, and this cryptic lifestyle renders caecilians among the least familiar amphibians. Modern caecilians live in the tropics of South and Central America, Africa, and southern Asia. Caecilians feed on small subterranean creatures such as earthworms. The body is cylindrical and often darkly coloured, and the skull is bullet-shaped and strongly built. Caecilian heads have several unique adaptations, including fused cranial and jaw bones, a two-part system of jaw muscles, and a chemosensory tentacle in front of the eye. The skin is slimy and bears ringlike markings or grooves and may contain scales.
Rhinatrematidae is a family of caecilians, also known as the Neotropical tailed caecilians, American tailed caecilians. or beaked caecilians. They are found in the equatorial countries of South America.
Ichthyophis garoensis, the Garo Hills caecilian, is a species of caecilian found in Assam and Meghalaya in north-eastern India. The Husain's caecilian Ichthyophis husaini was until 2016 considered a separate species. It is a subterranean caecilian that lives in the moist leaf-litter of tropical forests. It is typically found close to streams and other waterbodies.
Gegeneophis ramaswamii, common names Tenmalai caecilian, Tenmalai blind caecilian, Ramaswami's caecilian, and forest caecilian is a species of caecilian. It is endemic to the southern portion of the Western Ghats, India, and is recorded from Kerala and Tamil Nadu. The specific name ramaswamii honours L. S. Ramaswami, an Indian herpetologist.
Atretochoana eiselti is a species of caecilian originally known only from two preserved specimens discovered by Sir Graham Hales in the Brazilian rainforest, while on an expedition with Sir Brian Doll in the late 1800s, but rediscovered in 2011 by engineers working on a hydroelectric dam project in Brazil. Until 1998, it was known only from the type specimen in the Naturhistorisches Museum, Vienna. Originally placed in the genus Typhlonectes in 1968, it was reclassified into its own monotypic genus, Atretochoana, in 1996. It was also found to be more closely related to the genus Potamotyphlus than Typholonectes. The species is the largest of the few known lungless tetrapods, and the only known lungless caecilian.
Boulengerula fischeri is a species of caecilian in the family Herpelidae. It is endemic to Rwanda and only known from around its type locality near Cyangugu, southwestern Rwanda. The specific name fischeri honours Eberhard Fischer, a German botanist who has worked with Rwandan fauna and flora. Common name Fischer's African caecilian has been coined for it. Live animals have the appearance of "live pink spaghetti".
Brasilotyphlus is a genus of caecilians in the family Siphonopidae. It was considered monotypic, containing only the species Brasilotyphlus braziliensis. However, two recently described species, Brasilotyphlus guarantanus and Brasilotyphlus dubium, have been placed in this same genus. Both species have only been recorded from Brazilian Amazonia. This genus has also been suggested as paraphyletic to Microcaecilia.
Chthonerpeton indistinctum is a species of caecilian in the family Typhlonectidae. It is found in northeastern Argentina, Paraguay, Uruguay, and southeastern Brazil. The common name Argentine caecilian has been coined for it.
Dermophis oaxacae, also known Oaxacan caecilian, is a species of caecilian in the family Dermophiidae. It is endemic to southwestern Mexico and occurs on the Pacific slopes and the Balsas depression in the states of Jalisco, Michoacán, Guerrero, Oaxaca, and Chiapas.
Microcaecilia is a genus of caecilians in the family Siphonopidae.
Microcaecilia taylori is a species of caecilian in the family Siphonopidae. It is known from two widely separated populations, one in southern Suriname and other one in Pará, Brazil, south of the Amazon River. It is not clear whether the gap is real or whether the populations south of the Amazon River represent a distinct species. Microcaecilia taylori was confused with Microcaecilia marvaleewakeae before the latter was described in 2013.
Schistometopum thomense is a species of amphibian in the family Dermophiidae, endemic to São Tomé and Ilhéu das Rolas. It is found in most soils on São Tomé, from tropical moist lowland forests to coastal coconut plantations. It is absent only from the driest northern areas of the island. It is typically around 30 cm (12 in) in length, and is often bright yellow. The size of S. thomense can vary throughout São Tomé, however, and it is the only known caecilian to follow Bergmann's rule, which states that a decreasing temperature due to factors such as increasing altitude will cause an increase in the body size of endothermic vertebrate species. The island of São Tomé is a massive shield volcano, and it therefore has differing altitudes throughout the island, potentially resulting in the size diversity of S. thomense. This species may be referred to as the São Tomé caecilian, as the Agua Ize caecilian, or as the island caecilian, or by the local name of cobra bobo.
Siphonops annulatus, the ringed caecilian, is a species of caecilian in the family Siphonopidae from South America. It might have the broadest known distribution among terrestrial caecilian species.
Sylvacaecilia is a monotypic genus of caecilian in the family Grandisoniidae. The only species is Sylvacaecilia grandisonae, also known as the Aleku caecilian or Ethiopian caecilian. It is endemic to southwestern Ethiopia and known from the Gambela, Oromia, and Southern Nations, Nationalities, and Peoples' Regions.
Typhlonectes compressicauda, the Cayenne caecilian, is a species of amphibian in the family Typhlonectidae that lives in water. It is found in Amazonian Brazil, Peru, and Colombia as well as in Guyana and French Guiana, and likely Suriname, and according to some sources, Venezuela. It is an aquatic caecilian that inhabits permanent rivers and marshes mainly in the lowland forest zone.
Ichthyophis biangularis, the angular caecilian or Metang caecilian, is a species of amphibian in the family Ichthyophiidae endemic to Borneo (Malaysia): it is only known from its type locality, Mount Matang in Sarawak, where the holotype was collected in 1872 by Alfred Hart Everett. New specimens were collected from the type locality only in 2009. In addition, one larval sample was collected from the same region and identified as likely Ichthyophis biangularis using genetic methods.
Rhinatrema is a genus of caecilians in the family Rhinatrematidae. Their common name is two-lined caecilians. The genus is known from the Guyanas and adjacent Brazil. Most Rhinatrema are known to inhabit and live in areas of tropical forests where there is an abundance of dense, dead vegetation matter.
The Siphonopidae are the family of common caecilians. They are found in Central and South America. Like other caecilians, they superficially resemble worms or snakes.
Marvalee Hendricks Wake is an American zoologist and professor at the University of California, Berkeley, known for her research in the biology of caecilians and vertebrate development and evolution. A 1988 Guggenheim Fellow, she has served as president of the American Institute of Biological Sciences, the American Society of Ichthyologists and Herpetologists, Society for Integrative and Comparative Biology, International Union of Biological Sciences, and the International Society of Vertebrate Morphology. She is a fellow of the American Association for the Advancement of Science and the California Academy of Sciences, and is a member of the American Academy of Arts and Sciences.
