Eel

Eels Temporal range: Cenomanian–recent[1] PreꞒ Ꞓ O S D C P T J K Pg N
Anguilla japonica
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Superorder:	Elopomorpha
Order:	Anguilliformes L. S. Berg, 1943
Type genus
Anguilla Garsault, 1764[2]
Suborders
Protanguilloidei Synaphobranchoidei Muraenoidei Chlopsoidei Congroidei Moringuoidei Saccopharyngoidei Anguilloidei

Eels are ray-finned fish belonging to the order Anguilliformes (/æŋˈɡwɪlɪfɔːrmiːz/), which consists of eight suborders, 20 families, 164 genera, and about 1000 species.^[3][4] Eels undergo considerable development from the early larval stage to the eventual adult stage and are usually predators.

The term "eel" is also used for some other eel-shaped fish, such as electric eels (genus Electrophorus), swamp eels (order Synbranchiformes), and deep-sea spiny eels (family Notacanthidae). However, these other clades, with the exception of deep-sea spiny eels, whose order Notacanthiformes is the sister clade to true eels, evolved their eel-like shapes independently from the true eels. As a main rule, most eels are marine. Exceptions are the catadromous genus Anguilla and the freshwater moray,^[5] which spend most of their life in freshwater, the anadromous rice-paddy eel, which spawns in freshwater, and the freshwater snake eel Stictorhinus.^[6]