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. They are elongated fish with snake-like bodies, their long dorsal, caudal and anal fins forming a continuous fringe. They are catadromous fish, spending their adult lives in fresh water, but migrating to the ocean to spawn. Eels are an important food fish and some species are now farm-raised, but not bred in captivity. Many populations in the wild are now threatened, and Seafood Watch recommend consumers avoid eating anguillid eels.
The superorder Elopomorpha contains a variety of types of fishes that range from typical silvery-colored species, such as the tarpons and ladyfishes of the Elopiformes and the bonefishes of the Albuliformes, to the long and slender, smooth-bodied eels of the Anguilliformes. The one characteristic uniting this group of fishes is they all have leptocephalus larvae, which are unique to the Elopomorpha. No other fishes have this type of larvae.
The cusk-eel family, Ophidiidae, is a group of marine boney fishes in the order Ophidiiformes. The scientific name is from the Greek ophis meaning "snake", and refers to their eel-like appearance. True eels, however, diverged from other ray-finned fish during the Jurassic, while cusk-eels are part of the Percomorpha clade, along with tuna, perch, seahorses, and others. Unlike true eels of the order Anguilliformes, cusk-eels have ventral fins that are developed into a forked barbel-like organ below the mouth. In the true eels by contrast, the ventral fins are never well-developed and usually missing entirely.
The Samoa sawtooth eel, Serrivomer samoensis, is a sawtooth eel of the genus Serrivomer, found in the southwest Pacific at depths between 500 and 2,000 m. Their length is up to 75 cm.
Snipe eels are a family, Nemichthyidae, of eels that consists of nine species in three genera. They are pelagic fishes, found in every ocean, mostly at depths of 300–600 m but sometimes as deep as 4000 m. Depending on the species, adults may reach 1–2 m (39–79 in) in length, yet they weigh only 80-400 g. They are distinguished by their very slender jaws that separate toward the tips as the upper jaw curves upward. The jaws appear similar to the beak of the bird called the snipe. Snipe eels are oviparous, and the juveniles, called Leptocephali, do not resemble the adults but have oval, leaf-shaped and transparent bodies. Different species of snipe eel have different shapes, sizes and colors. The similarly named bobtail snipe eel is actually in a different family and represented by two species, the black Cyema atrum and the bright red Neocyema erythrosoma.
Longneck eels or neck eels are a family, Derichthyidae, of eels. They are pelagic fishes, found in the middle and depths of most oceans. The name comes from Greek deres meaning "neck" and ichthys meaning "fish".
Nettastomatidae, the duckbill eels or witch eels are a family of eels. The name is from Greek netta meaning "duck" and stoma meaning "mouth".
The Anguilloidei are a suborder of the order Anguilliformes containing three families:
Leptocephalus is a genus that was used for species of larval eels, called leptocephali, that were thought to be new fish species, or whose adult eel species were not known. Leptocephali differ so much in appearance from their adults that the larvae and adults of eels are not easily matched, and when first discovered, leptocephali were thought to be a distinct type of fishes, but not eels. Because of this, the genus designation of Leptocephalus was used for a while for unidentified leptocephali even after it was known that these were the larvae of eels thus becoming a "wastebasket taxon", but this practice is no longer used. Examples of marine congrid larvae, found in the western Indian Ocean and the Red Sea that were named this way are listed below. Only two species in two families are currently treated as having any validity, though the validity of L. bellottii is strongly in doubt.
Stemonidium hypomelas is a species of deep-sea eel in the family Serrivomeridae, originally described from a 171-mm specimen taken from a depth of around 1,000 m near Niihau Island, Hawaii in 1902. It can be distinguished from the related sawtooth eels by its reduced dentition, which more resemble those of the snipe eel. It is of no significance to fisheries.
The Colocongridae, the worm eels or short-tail eels are a family of eels, containing a single genus, Coloconger.
An eel is a 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 most are predators.
Serrivomer is a genus of deep-sea eel in the family Serrivomeridae. It contains ten described species. Member species are distributed widely, being found in the Atlantic, Pacific and Indian Oceans. The smallest species in this genus is Serrivomer jesperseni, which has a maximum length of 40.6 cm; the largest species in this genus is Serrivomer beanii with a maximum length of 78 cm. Most members reach a maximum length of 60–70 cm,
The Gilbert's garden eel, also known as the Gilbert's conger and the sharpnose conger, is an eel in the family Congridae. It was described by James Douglas Ogilby in 1898, originally under the genus Congrellus. It is a tropical, marine eel which is known from the eastern central and southeastern Pacific Ocean, including the Gulf of California, Costa Rica, El Salvador, Ecuador, Guatemala, Mexico, Honduras, Nicaragua, Panama, and Colombia. It is a benthic and nocturnal species, and inhabits sand flats in reefs, bays and coves at a depth range of 1–100 metres. It burrows into sand during the day and emerges to forage during the night. Males can reach a maximum total length of 27 centimetres.
The tropical conger, also known as the Scheele's conger, is an eel in the family Congridae. It was described by Pehr Hugo Strömman in 1896, originally under the genus Leptocephalus. It is a tropical, marine eel which is known from the Indo-Pacific, including Natal and Mozambique. It inhabits reefs in lagoons, and is known to dwell at a depth of 9 metres. Males can reach a maximum total length of 20 centimetres (7.9 in).
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 thread eel is an eel in the family Nemichthyidae. It was described by Marie-Louise Bauchot in 1959. It is a marine, temperate water-dwelling eel which is known from the Indo-Pacific and Chile in the southwestern Pacific Ocean. It is known to dwell at a depth of 1,750 metres (5,740 ft).
Serrivomer garmani is an eel in the family Serrivomeridae. It was described by Léon Bertin in 1944. It is a marine, deep water-dwelling eel which is known from the Indian Ocean. It is known to dwell at a depth range of 30 to 2,250 metres.
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).
Serrivomer sector, known commonly as the sawtooth eel, the saw-tooth snipe or the deep-sea eel, is an eel in the family Serrivomeridae. It was described by Samuel Garman in 1899. It is a marine, deep water-dwelling eel which is known from the eastern and western Pacific Ocean, including Japan, Chile, and California, USA. It dwells at a depth range of 0 to 3,243 metres, most often around 305 metres (1,001 ft). Males can reach a maximum total length of 76 centimetres (30 in).
