Goblin shark

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iGoblin shark

Conservation status
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Chondrichthyes
Subclass: Elasmobranchii
Order: Lamniformes
Family: Mitsukurinidae
Genus: Mitsukurina
Species: M. owstoni
Binomial name
Mitsukurina owstoni
Jordan, 1898

The goblin shark, Mitsukurina owstoni, is a rarely seen species of shark. It is notable for its long beak-like rostrum projecting forward of the jaws, its long, protruding jaws, and its pink color. When the jaws are retracted, the shark resembles a pink grey nurse shark, Carcharias taurus, with an unusually long nose. The goblin shark is the sole known living member of the family Mitsukurinidae; the relatively plentiful fossil record includes another two dozen or so species in two (extinct) genera, Scapanorhynchus and Anomotodon.

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[edit] Discovery

The goblin shark was first caught by Japanese fishermen in the "Black Current" off the coast of Yokohama in 1898. The fishermen called the animal "tenguzame", which, in Japanese, means "goblin shark". This specimen was a 3.5 foot male.[1]

A goblin shark was kept by the Tokai University of Japan; the fish in question died after a week.

[edit] Distribution and habitat

Only about 45 specimens have been described in the scientific literature. They generally live at a depth of up to 1,200 m, on the sea bottom. Half have been found off Japan, including the first one described (David Starr Jordan, 1898).

They have been found in the western Atlantic off French Guiana; in the eastern Atlantic in the Bay of Biscay and off Madeira and Portugal; in the waters off South Africa, and in the western Pacific Ocean off Japan and Australia.

[edit] Anatomy and appearance

Dead specimen.
Enlarge
Dead specimen.

Goblin sharks lack a nictitating membrane. They have small dorsal fins, low and rounded. The anal fin is larger than dorsal fins, the pectoral fins are small, the pelvic fins are large, bigger than the dorsal fins. They have no precaudal pit, and no keels.

Computer model, showing the natural pink color.
Enlarge
Computer model, showing the natural pink color.

The pink coloration, unique among sharks, is due to blood vessels underneath a semi-transparent skin, which bruises easily, thereby causing the coloring. The fins have a bluish appearance. As with thresher sharks and other members of the order Lamniformes, the upper lobe of the tail is much longer than the lower lobe. Typical specimens are 2 to 3 m (6.6 to 9.8 ft) in length; the largest seen so far was 3.85 m (12.6 ft) in length. Several are preserved at the Australian Museum.

The front teeth are long and smooth-edged, while the rear teeth are adapted for crushing. Reproduction is ovoviviparous.

Interestingly, up to 25% of the goblin shark's body weight can be its liver. It is currently not understood why the shark has such a large liver.[2]

[edit] Diet

Goblin sharks feed on deep-sea rockfish ( Helicolenus dactylopterus, the jacopever, was found in one specimen), octopuses and crabs, most likely by sensing the presence of prey with electro-sensitive organs in the beak, suddenly protruding the jaws, creating a sucking motion with a tongue-like muscle, and using the teeth to hold onto the victim.

[edit] Trivia

The goblin shark is one of twenty marine animals in Zoo Tycoon 2: Marine Mania.

[edit] References

  1. ^ The Goblin Shark
  2. ^ The Goblin Shark

[edit] External links