The Atlantic halibut is a flatfish of the family Pleuronectidae. They are demersal fish living on or near sand, gravel or clay bottoms at depths of between 50 and 2,000 m (160 and 6,600 ft). The halibut is among the largest bony fish in the world. The native habitat of the Atlantic halibut is the temperate waters of the northern Atlantic, from Labrador and Greenland to Iceland, the Barents Sea and as far south as the Bay of Biscay. It is the largest flatfish in the Atlantic and one of the largest species of flatfish in the world, reaching lengths of up to 4.7 m (15 ft) and weights of 320 kg (710 lb). Its lifespan can reach 50 years.