The Notacanthiformes /nɒtəˈkænθɪfɔːrmz/ are an order of deep-sea ray-finned fishes, consisting of the families Halosauridae and Notacanthidae (spiny eels).[1]

Temporal range: Late Cretaceous–Recent[1]
Notacanthus chemnitzii.jpg
Snubnosed Spiny Eel, Notacanthus chemnitzii
Scientific classification e
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Superorder: Elopomorpha
Order: Notacanthiformes
L. S. Berg, 1947




The order is of relatively recent vintage; Fishes of the World (2006) lists it as the suborder Notacanthoidei of Albuliformes.[2] The notacanthiforms are much more eel-like than the albuliforms; for instance, the caudal fin has disappeared.

Fish of the order are found in oceans worldwide, at depths from 120 to 4,900 metres (390 to 16,080 ft). They are elongated fish, although not as much so as the true eels. They typically feed on slow-moving or sessile animals, such as molluscs, echinoderms, and sea anemones. Like the true eels, they have a leptocephalus larva that floats in the surface waters before transforming into an adult. Unusually, the larva can often be larger than the adult.[3]


  1. ^ a b Froese, Rainer, and Daniel Pauly, eds. (2009). "Notacanthiformes" in FishBase. January 2009 version.
  2. ^ Joseph S. Nelson (29 April 1994). Fishes of the World. John Wiley & Sons. ISBN 0-471-54713-1.
  3. ^ McCosker, John F. (1998). Paxton, J.R.; Eschmeyer, W.N. (eds.). Encyclopedia of Fishes. San Diego: Academic Press. p. 86. ISBN 0-12-547665-5.