Echinorhinus

Echinorhinus is the only extant genus in the family Echinorhinidae. Echinorhinidae are traditionally classified in the order Squaliformes, together with kitefin and gulper sharks. Most phylogenetic studies based on molecular data imply that this is incorrect, however, and that they are in fact more closely related to Angel sharks and sawsharks..The phylogenetic placement of Echinorhinidae has remained ambiguous in both morphological and molecular studies, either being included within Squaliformes, considered sister to Squaliformes, or placed in a separate group with Sawsharks (Pristiophoriformes) or Angel sharks (Squatiniformes). For this reason they are sometimes given their own order, Echinorhiniformes. The name is from Greek echinos meaning 'spiny' and rhinos meaning 'nose'. This genus includes two extant species of uncommon, little-known sharks. Both species are relatively large sharks, at 3.1 to 4.0 m (10.2 to 13.1 ft) in body length. They are characterized by a short nose and by rough, thorn-like dermal denticles scattered over its body, some of which may be fused together. They have no anal fin. Two small spineless dorsal fins are positioned far back. They are ovoviviparous, with the mother retaining the egg-cases inside her body until they hatch, producing litters up to 24 pups. They feed on smaller sharks, smaller bony fish, and on crabs and cephalopods. These sharks are found worldwide in cold temperate to tropical seas from the surface down to 900 m (3,000 ft).