These are large sharks with very prominent jaws and teeth. Yet despite their appearance, they are harmless. There are 4 species belonging to 2 genera. Their body is cylindrical, slightly compressed and moderately stout. Sand tigers possess a very pointed snout, with small eyes. Both dorsal fins are of similar size, as is the anal fin. The origin of the first dorsal fin is over or behind the position of the pectoral fins. Sand tigers are found in tropical to cold, temperate waters, both inshore and deeper waters, even on the upper continental slopes down to about 1500m. Sand tiger sharks are known to gulp air to increase their buoyancy. They feed primarily on fishes. It is known, for at least one species, Caracharias taurus, that they hunt in groups. They show an ovoviviparous style of reproduction (aplacental viviparity) with a unique form of embryological phagism, the so-called intra-uterine cannibalism where older embryos feed on siblings of earlier stages.
Typical species of the family of "Sandtiger sharks":
Grey nurse shark
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