Eels are any of several long, thin, bony fishes of the order Anguilliformes. They have a catadromous life cycle, that is: at different stages of development migrating between inland waterways and the deep ocean. Because fishermen never caught anything they recognized as young eels, the life cycle of the eel was long a mystery. Of particular interest has been the search for the spawning grounds for the various species of eels, and identifying the population impacts of different stages of the life cycle.
Protopterus is the genus of four species of lungfish found in Africa. Protopterus is considered the sole genus in the family Protopteridae, which is grouped with Lepidosiren in the order Lepidosireniformes.
Ophichthidae is a family of fish in the order Anguilliformes, commonly known as the snake eels. The term "Ophichthidae" comes from Greek ophis ("serpent") and ichthys ("fish"). Snake eels are also burrowing eels. They are named for their physical appearance, as they have long, cylindrical, snake-like bodies. This family is found worldwide in tropical to warm temperate waters. They inhabit a wide range of habitats, from coastal shallows and even rivers, to depths below 800 m (2,600 ft). Most species are bottom dwellers, hiding in mud or sand to capture their prey of crustaceans and small fish, but some are pelagic.
The Anguillidae are a family of ray-finned fish that contains the freshwater eels. All the extant species and six subspecies in this family are in the genus Anguilla, and are elongated fish of snake-like bodies, with long dorsal, caudal and anal fins forming a continuous fringe. They are catadromous, spending their adult lives in freshwater, but migrating to the ocean to spawn.
Ilyophis is a genus of marine ray-finned fishes belonging to the family Synaphobranchidae, the cutthroat eels. These eels are found in the Atlantic, Indian and Pacific Oceans.
The giant mottled eel, also known as the marbled eel, is a species of tropical anguillid eel that is found in the Indo-Pacific and adjacent freshwater habitats.
The marbled electric ray is a species of electric ray in the family Torpedinidae found in the coastal waters of the eastern Atlantic Ocean from the North Sea to South Africa. This benthic fish inhabits rocky reefs, seagrass beds, and sandy and muddy flats in shallow to moderately deep waters. It can survive in environments with very little dissolved oxygen, such as tidal pools. The marbled electric ray has a nearly circular pectoral fin disc and a muscular tail that bears two dorsal fins of nearly equal size and a large caudal fin. It can be identified by the long, finger-like projections on the rims of its spiracles, as well as by its dark brown mottled color pattern, though some individuals are plain-colored. Males and females typically reach 36–38 cm (14–15 in) and 55–61 cm (22–24 in) long respectively.
The brown-marbled grouper or tiger grouper is a benthic marine fish which belongs to the family Serranidae or also known as the groupers.
Eels are ray-finned fish belonging to the order Anguilliformes, which consists of eight suborders, 20 families, 164 genera, and about 1000 species. Eels undergo considerable development from the early larval stage to the eventual adult stage and are usually predators.
The whitemargin moray or the white-edged moray, Gymnothorax albimarginatus, is a species of marine fish in the family Muraenidae.
Callechelys bilinearis, the twostripe snake eel, is an eel in the family Ophichthidae. It was described by Robert H. Kanazawa in 1952. It is a marine, tropical eel which is known from the western and southeastern Atlantic Ocean, including Bermuda, the West Indies, Lesser Antilles, St. Helena Island and Ascension Island. It dwells at a depth range of 0 to 22 metres, most often at around 0 to 5 metres. Males can reach a maximum total length of 172.4 centimetres (67.9 in).
Callechelys catostoma, the black-striped snake eel or dark band snake eel,) is an eel in the family Ophichthidae. It was described by Johann Gottlob Theaenus Schneider and Johann Reinhold Forster in 1801. It is a tropical, marine eel which is known from the Indo-Pacific, including the Red Sea, East Africa, the Society Islands, the Ryukyu Islands, and Lord Howe Island. It dwells at a depth range of 1–32 metres, and inhabits reefs. It burrows into loose gravel and sand. Males can reach a maximum total length of 85 centimetres (33 in).
Callechelys eristigma, the spotted ridgefin eel, is an eel in the family Ophichthidae. It was described by John E. McCosker and Richard Heinrich Rosenblatt in 1972. It is a marine, tropical eel which is known from the eastern central Pacific Ocean, including Costa Rica, Mexico, and Panama. It dwells at a depth range of 5 to 25 metres, and inhabits benthic sediments of rock and sand. Males can reach a maximum standard length of 113 centimetres (44 in).
Callechelys galapagensis, the Galapagos ridgefin eel, is an eel in the family Ophichthidae. It was described by John E. McCosker and Richard Heinrich Rosenblatt in 1972. It is a tropical, marine eel which is known from four specimens collected from the Galapagos Islands, in the southeastern Pacific Ocean. It inhabits coral, sand and rock.
Callechelys guineensis, the shorttail snake eel, is an eel in the family Ophichthidae. It was described by Balthazar Osório in 1893, originally under the genus Ophichthys. It is a marine, tropical eel which is known from the western and eastern Atlantic Ocean, including Florida, USA, Puerto Rico, Venezuela, the Bahamas, Saint Barthélemy, Senegal, Lesser Antilles, and Cape Verde. It dwells at a depth range of 4 to 35 metres, and inhabits the continental shelf, where it forms burrows in sand and mud. Males can reach a maximum total length of 108 centimetres (43 in).
Callechelys leucoptera is an eel in the family Ophichthidae. It was described by Jean Cadenat in 1954. It is a tropical, marine eel which is known from the eastern Atlantic Ocean, including Senegal to Côte d'Ivoire. It is known to dwell at a depth of 45 metres. It inhabits shallow waters where it forms burrows in the sand, which are sometimes exposed during low tide. Males can reach a maximum total length of 73 centimetres, but more commonly reach a TL of 50 centimetres.
Callechelys lutea, the freckled snake eel or yellow-spotted snake eel, is an eel in the family Ophichthidae. It was described by John Otterbein Snyder in 1904.
Callechelys muraena, the blotched snake eel, is an eel in the family Ophichthidae. It was described by David Starr Jordan and Barton Warren Evermann in 1887. It is a rare tropical, marine eel which is known from the western and northwestern Atlantic Ocean, including the United States, the Gulf of Mexico, the Yucatan Peninsula, and Canada. It dwells at a depth range of 27–115 metres. Males can reach a maximum total length of 60 centimetres.
Callechelys papulosa, the blistered snake eel, is an eel in the family Ophichthidae. It was described by John E. McCosker in 1998. It is a tropical, marine eel which is known from Papua New Guinea, in the western central Pacific Ocean. It is known to dwell at a depth of 10 metres, and to inhabit regions of sand and grass. Males can reach a maximum total length of 55.1 centimetres.
Callechelys springeri, the ridgefin eel, is an eel in the family Ophichthidae. It was described by Isaac Ginsburg in 1951, originally under the genus Gordiichthys. It is a marine, tropical eel which is known from the eastern Gulf of Mexico, in the western Atlantic Ocean. It dwells at a depth range of 22 to 36 metres. Males can reach a maximum total length of 80.1 centimeters (31.5 in).
