Carcharias

Carcharias is a genus of sharks in the family Odontaspididae, within the order Lamniformes. The genus currently has one living representative, Carcharias taurus, commonly known as the sand tiger shark or gray nurse shark in parts of its range. Fossil records indicate several extinct species have been assigned to Carcharias, illustrating a broader historical diversity.

Carcharias taurus is a relatively bulky, elongated shark with a pointed snout and a gray-brown dorsal surface fading to a lighter ventral side. Adults can reach lengths of about 3 meters (approximately 10 feet). Its teeth are long and narrow, and the jaws are highly protrusible, so the teeth are often visible even when the mouth is closed, giving the animal a distinctive appearance.

Habitat and distribution are wide but show regional variability. The species occurs in subtropical and warm-temperate seas worldwide, commonly near continental shelves, in bays, lagoons, and around coral reefs. Juveniles frequently inhabit shallow inshore waters, while adults may be found in deeper offshore regions or near the bottom. It is generally a slow-moving predator that feeds on small fish and squid, but will take larger prey when available.

Reproduction is ovoviviparous, with embryos developing inside eggs that hatch within the female and pups born live. Litter sizes are relatively small, and the species is characterized by a slower reproductive rate, which can limit population recovery after declines. Lifespan estimates place maturity in early adulthood, with longevity extending into multiple decades.

Conservation status is of concern in many regions. The IUCN lists Carcharias taurus as Vulnerable globally, with local protections in various countries due to fishing pressure, bycatch, and habitat degradation.