Taxon Description (Wikipedia)
Squaliformes is an order of sharks that includes about 80 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.
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