The eel is a long, thin bony fish of the order Anguilliformes. The species has 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 a mystery for a very long period of scientific history.
The Anguillidae are a family of ray-finned fish that contains the freshwater eels. Eighteen of the 19 extant species and six subspecies in this family are in the genus Anguilla, and all 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.
The New Zealand longfin eel, also known as ōrea, is a species of freshwater eel that is endemic to New Zealand. It is the largest freshwater eel in New Zealand and the only endemic species – the other eels found in New Zealand are the native shortfin eel, also found in Australia, and the naturally introduced Australian longfin eel. Longfin eels are long-lived, migrating to the Pacific Ocean near Tonga to breed at the end of their lives. They are good climbers as juveniles and so are found in streams and lakes a long way inland. An important traditional food source for Māori, who name them ōrea, longfin eel numbers are declining and they are classified as endangered, but over one hundred tonnes are still commercially fished each year.
The mottled eel, also known as the African mottled eel, the Indian longfin eel, the Indian mottled eel, the long-finned eel or the river eel, is a demersal, catadromous eel in the family Anguillidae. It was described by John McClelland in 1844. It is a tropical, freshwater eel which is known from East Africa, Bangladesh, Andaman Islands, Mozambique, Malawi, Sri Lanka, Sumatra, and Indonesia and recently from Madagascar. The eels spend most of their lives in freshwater at a depth range of 3–10 metres, but migrate to the Indian Ocean to breed. Males can reach a maximum total length of 121 centimetres and a maximum weight of 7,000 grams. The eels feed primarily off of benthic crustaceans, mollusks, finfish and worms.
The barred moray, also known as the banded moray, the dark-banded eel, the girdled moray, the girdled reef eel, the many banded moray eel, the ringed moray, the ringed reef moray, the striped moray and the zebra eel,) is a moray eel of the family Muraenidae. It was described by John Richardson in 1845, originally under the genus Muraena. It is a marine, tropical eel which is known from the Indo-Pacific, including the Red Sea, East Africa, the Hawaiian Islands, the Marquesan Islands, the Tuamotus Islands, the Ryukyu Islands, and the Great Barrier Reef. It dwells at a depth range of 2 to 20 metres, and leads a benthic lifestyle in reefs and shallow lagoons. Males can reach a maximum total length of 72.3 centimetres (28.5 in).
Eels are ray-finned fish belonging to the order Anguilliformes, which consists of eight suborders, 19 families, 111 genera, and about 800 species. Eels undergo considerable development from the early larval stage to the eventual adult stage and are usually predators.
Echidna leucotaenia, the whiteface moray, also known as the white-banded moray eel, is a moray eel. It was described by Schultz in 1943. It is a tropical, marine and freshwater eel which is known from the Indo-Pacific, including East Africa, the Line Islands, the Tuamotu Islands, and Johnston Island. It dwells at a depth range of 0 to 24 metres, and leads a benthic lifestyle in reefs. Males can reach a maximum total length of 75 centimetres (30 in).
The Celebes longfin eel is an eel in the family Anguillidae. It was described by Johann Jakob Kaup in 1856. It is a tropical eel known from freshwaters in the Western Pacific, including Indonesia, the Philippines, New Guinea, and Western and American Samoa. The eels spend most of their lives in freshwater but migrate to the ocean to breed. Males can reach a maximum total length of 150 centimetres.
The Highlands long-finned eel is an eel in the family Anguillidae. It was described by Gilbert Percy Whitley in 1938. It is a tropical eel known from freshwaters in eastern New Guinea. The eels spend most of their lives in freshwater but migrate to the ocean to breed. Males can reach a maximum total length of 80 centimetres.
The Polynesian longfinned eel, also known as the Pacific long-finned eel, is an eel in the family Anguillidae. It was described by Johann Jakob Kaup in 1856. It is a tropical eel found in freshwaters in the Pacific, including Sulawesi, Indonesia; the Society Islands, and Pitcairn. The eels spend most of their lives in freshwater, but migrate to the ocean to breed. Males can reach a maximum total length of 100 centimetres, while females can reach a maximum TL of 165 centimetres and a maximum weight of 9,000 grams.
The mottled eel, also known as the African mottled eel, the Indian longfin eel, the Indian mottled eel, the long-finned eel or the river eel, is a demersal, catadromous eel in the family Anguillidae. It was described by John McClelland in 1844. It is a tropical, freshwater eel which is known from East Africa, Bangladesh, Andaman Islands, Mozambique, Malawi, Sri Lanka, Sumatra, and Indonesia and recently from Madagascar. The eels spend most of their lives in freshwater at a depth range of 3–10 metres, but migrate to the Indian Ocean to breed. Males can reach a maximum total length of 121 centimetres and a maximum weight of 7,000 grams. The eels feed primarily off of benthic crustaceans, mollusks, finfish and worms.
The Pacific shortfinned eel, also known as the Pacific shortfinned freshwater eel, the short-finned eel, and the South Pacific eel, is an eel in the family Anguillidae. It was described by Albert Günther in 1871. It is a tropical, freshwater eel which is known from western New Guinea, Queensland, Australia, the Society Islands, and possibly South Africa. The eels spend most of their lives in freshwater, but migrate to the Pacific Ocean to breed. Males can reach a maximum total length of 110 centimetres, but more commonly reach a TL of around 60 cm. The Pacific shortfinned eel is most similar to Anguilla australis, and Anguilla bicolor, but can be distinguished by the number of vertebrae.
The Oriental worm-eel, also known as the Oriental snake eel, the Oriental sand-eel or the finny sand-eel, is an eel in the family Ophichthidae. It was described by John McClelland in 1844, originally under the genus Dalophis. It is a tropical, marine and freshwater-dwelling eel which is known from the Indo-Western Pacific, including Somalia, South Africa, India, Papua New Guinea, Tahiti, French Polynesia, Indonesia, Oman, Palau, New Caledonia, the Philippines, Sri Lanka, Seychelles, and Vanuatu. It dwells at a depth range of 0 to 3 metres, and forms burrows in sand and mud sediments in estuaries, rivers, and inshore turbid waters. Males can reach a maximum total length of 36 centimetres (14 in), but more commonly reach a TL of 25 centimetres (9.8 in).
The longfin spotted snake eel is an eel in the family Ophichthidae. It was described by John E. McCosker and Richard Heinrich Rosenblatt in 1993. It is a marine, tropical eel which is known from Mexico, Costa Rica and Panama, in the eastern central Pacific Ocean. It dwells at a depth range of 44 to 64 metres, and inhabits sandy substrates. Males can reach a maximum total length of 51 centimetres.
The goldspotted eel, also known as the goldspotted snake eel or the dark-spotted snake eel, is an eel in the family Ophichthidae. It was described by Charles Alexandre Lesueur in 1825, originally under the genus Muraenophis. It is a marine, tropical eel which is known from the western and eastern Atlantic Ocean, including Bermuda, southern Florida, USA; the Bahamas, Santa Catarina, and Brazil. It dwells at a maximum depth of 15 metres (49 ft), and inhabits rocky and coral reefs. Males can reach a maximum total length of 110 centimetres (3.6 ft).
The Pacific snake eel is an eel in the family Ophichthidae. It was described by Johann Jakob Kaup in 1856, originally under the genus Muraenopsis. It is a marine, subtropical eel which is known from the eastern central and southeastern Pacific Ocean, including California, USA, Peru, the Gulf of California, Mexico, the Galapagos Islands, Colombia, Ecuador, Costa Rica, El Salvador, Honduras, Guatemala, Nicaragua, and Panama. It dwells at a maximum depth of 155 metres (509 ft), and forms burrows in mud and sand sediments. Males can reach a maximum total length of 115 centimetres (45 in), but more commonly reach a TL of 80 centimetres (31 in).
The rice-paddy eel is an eel in the family Ophichthidae. It was described by Francis Buchanan-Hamilton in 1822, originally in the genus Ophisurus. It is a tropical, marine eel which is known from the Indo-West Pacific, including Somalia, Tanzania, South Africa, southern India, Sri Lanka, Indonesia, Polynesia, Australia, Bangladesh, Cambodia, Kenya, Madagascar, the Philippines, Malaysia, Mozambique, Seychelles, Saudi Arabia, Taiwan, China, Thailand, Vietnam, and southern Yemen. It is an anadromous species and spawns in freshwater, often in rice paddies during the rainy season, earning it its common name. It also spends time in lagoons, estuaries and coastal rivers, in which it lives in burrows in the river bottom and bank. Males can reach a maximum total length (TL) of 100 centimetres, but more commonly reach a TL of 70 cm.
The Bean's sawtooth eel is an eel in the family Nemichthyidae. It was described by Theodore Gill and John Adam Ryder in 1883. It is a marine, deep water-dwelling eel which is known from throughout the Atlantic Ocean, the Indian Ocean, and the Western Pacific Ocean, including Iceland, South Africa, Réunion, and Australia. It dwells at a depth range of 0–5998 metres, and leads a solitary lifestyle. It migrates vertically at night. Males can reach a maximum total length of 78-80 centimetres, making it the largest sawtooth eel.
The short-tooth sawpalate is an eel in the family Serrivomeridae. It was described by Johannes Schmidt in 1916, originally under the genus Leptocephalus. It is a marine, deep water-dwelling eel which is known from the eastern central and western central Atlantic Ocean, including the Bahamas and Bermuda, as well as the Strait of Gibraltar, Cape Verde, Canada and the United States. It dwells at a depth range of 150 to 1,000 metres. Males can reach a maximum total length of 65 centimetres (26 in).
The Kaup's arrowtooth eel is an eel in the family Synaphobranchidae. It was described by James Yate Johnson in 1862. It is a marine, deep water-dwelling eel which is known from the Indo-Western Pacific and eastern and western Atlantic Ocean, including the Faroe Islands, Iceland, Cape Verde, the Western Sahara, Nigeria, Namibia, South Africa, Greenland, France, Saint Pierre and Miquelon, the United Kingdom, Ireland, the Philippines, Portugal, Spain, the Bahamas, Brazil, Canada, Cuba, Japan, Australia, Mauritania, Morocco, and Hawaii. It dwells at a depth range of 120 to 4,800 metres, most often between 400 and 2,200 metres, and inhabits the upper abyssal zone on the continental slope. It is intolerant of the temperatures of higher waters. Males can reach a maximum total length of 100 centimetres (39 in).
