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Squaliform

Squaliformes
Temporal range: Late Jurassic–Recent
Spiny dogfish.jpg
Spiny dogfish, Squalus acanthias
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Chondrichthyes
Subclass: Elasmobranchii
Superorder: Selachimorpha
Order: Squaliformes
Goodrich, 1909

The Squaliformes are an order of sharks that includes about 126 species in seven families.

Members of the order have two dorsal fins, which usually possess spines, no anal fin or nictitating membrane, and five gill slits. In most other respects, however, they are quite variable in form and size. They are found worldwide, from polar to tropical waters, and from shallow coastal seas to the open ocean.

Family Centrophoridae Bleeker, 1859 (gulper sharks)

Family Dalatiidae (J. E. Gray, 1851) (kitefin sharks)

Family Echinorhinidae Theodore Gill, 1862 (bramble sharks)

Family Etmopteridae Fowler, 1934 (lantern sharks)

Family Oxynotidae Gill, 1872 (rough sharks)

Family Somniosidae D. S. Jordan, 1888 (sleeper sharks)

Family Squalidae Blainville, 1816 (dogfish sharks)


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Wikipedia

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