Crocodile shark

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Crocodile shark
Conservation status
Near Threatened
Scientific classification
Kingdom: Animalia Phylum: Chordata Class: Chondrichthyes Subclass: Elasmobranchii Order: Lamniformes Family: Pseudocarchariidae Genus: Pseudocarcharias Species: P. kamoharai
Binomial name
Pseudocarcharias kamoharai (Matsubara, 1936)
Known range - dark blue Possible range - light blue

The crocodile shark, Pseudocarcharias kamoharai, the only member of the genus Pseudocarcharias (in turn the only member of its family Pseudocarchariidae), is a shark found in the tropical and subtropical waters of all oceans, at depths down to 590 m. It can exceed 1 m in length.

Contents 1 Distribution and habitat 2 Anatomy and appearance 3 Diet 4 Behavior 5 Reproduction 6 Importance to humans 7 Taxonomy 8 References

[edit] Distribution and habitat

The crocodile shark is an oceanic species usually found offshore and far from land but sometimes occurring inshore.

[edit] Anatomy and appearance

It is a medium-sized spindle-shaped shark with very large eyes lacking a nictitating membrane, long gill slits extending onto the dorsal surface of the head, lanceolate teeth, weak keel and precaudal pits on the caudal peduncle. The dorsal fins are small and low, with the second dorsal fin less than half the size of the first but larger than the anal fin. The pectoral fin is broad and rounded.

The coloration is light or dark grey above, paler below, fins white-edged, sometimes with small white spots on the body, and a white blotch between the mouth and the gill slits.

[edit] Diet

Their diet is small pelagic bony fishes, squids and shrimps .

[edit] Behavior

The behavior of the crocodile shark is not well known, but it is believed to be a fast-swimming shark, probably capable of leaping out of the water. It is a pelagic shark. Its large eyes might indicate either nocturnal activity or feeding at great depths.

[edit] Reproduction

Reproduction is ovoviviparous, embryos feeding on yolk sac and other ova produced by the mother, with up to 4 young in a litter.

[edit] Importance to humans

Although the crocodile shark is not considered dangerous to humans, its powerful jaws, jaw muscles and teeth invite respect. The flesh is not utilized except for its large, squalene-rich liver. It is fished by longlines off Japan but not significantly consumed.

[edit] Taxonomy

The English name is derived from the Japanese name for this animal mizu wani, which literally means water crocodile.

[edit] References

• "Pseudocarcharias kamoharai". FishBase. Ed. Ranier Froese and Daniel Pauly. May 2006 version. N.p.: FishBase, 2006.
• Animaldiversity