Odontaspis taurus Tooth Sand Tiger Shark (3) Dogfishes Cartilaginous Fishes Chondrichthyes Selachians Elasmobranchs

Sand Tiger Shark Tooth Odontaspis taurus Dogfishes Cartilaginous Fishes Chondrichthyes Selachians Elasmobranchs Odontaspididae.
Measures: diagonal mm 27, height mm 26, base mm 15, rare, with minor cusps.
Common name: Sand Tiger Shark, Blue Grey Nurse Shark Spotted or Ragged-Tooth Shark.
Syn. Eugomphodus taurus, Carcharias arenarius, Carcharias taurus or Carcharias tricuspidatus.
Also available Shark Teeth Necklaces, single or in lots, at this link.

The Sand Tiger Shark, Grey Nurse Shark, Spotted Ragged-Tooth Shark, or Blue-Nurse Sand Tiger (Carcharias taurus) is a large Shark inhabiting the subtropical and temperate coastal waters of the world with different names depending on the place in which it lives. It is present all over the world, in the Atlantic, in the Pacific and in the Indian Ocean. To the detriment of its scary appearance and its ability to swim, it is a relatively placid and slow shark that has not reported human casualties. Because of its large size and docile temperament, the O. taurus is commonly exhibited in aquariums all over the world, thanks to its tolerance to imprisonment.
It is sometimes confused with the Carcharhinus leucas, due to the English name bull shark. Despite its name, it is not related to the tiger shark Galeocerdo cuvier; however, he is a cousin of the great white shark Carcharodon carcharias.
This species has a sharp and pointed head. The body is massive and voluminous in gray with reddish brown spots on the back; it has two large dorsal fins, the tail is elongated with a long upper lobe. It grows up to a length of 320 cm. The male reaches maturity when it is 210 cm large and the female at 220 cm.
Usually this shark swims with its mouth open and shows three rows of protruding teeth, with smooth and pointed edges. The teeth of these sharks do not have transverse serrations (like many other sharks), but they have a wide and smooth main cusp with a small cusp on each side of the main cusp. The upper anterior teeth are separated from the teeth on the side of the mouth by small intermediate teeth.
The sand tiger shark is a nocturnal predator. His diet consists of bony fish, crustaceans, squid and other sharks. It typically gathers in coastal waters, at depths of 10-60 meters, although it has been seen in greater depths. It often hides in pits and caves during the day and goes out at night to eat. Research indicates that generally the shark remains within a kilometer from the place of aggregation, and near the bottom of the ocean, hence its name tiger shark of the sand.
It is the only known shark able to swallow the air and store it in the stomach, allowing it to maintain an almost neutral buoyancy that helps it to hunt in a motionless and silent way.
Reproduction is ovoviviparous. The female has two wombs. During pregnancy, the most developed embryo will feed on its siblings, a reproductive strategy known as intrauterine cannibalism, that is, "embryophagy" or, more colorfully, adelphophagy - literally "eating one's brother".