The beluga or European sturgeon (Huso huso) is a species of anadromous fish in the sturgeon family (Acipenseridae) of order  Acipenseriformes. It is found primarily in the Caspian and Black Sea basins, and occasionally in the Adriatic Sea. Heavily fished for the female's valuable roe—known as beluga caviar— the beluga is a huge and late-maturing fish that can live for 118 years. The species' numbers have been greatly reduced by overfishing and poaching, prompting many governments to enact restrictions on its trade. The most similar to the Huso huso beluga is the Huso dauricus kaluga, also referred to as the "river beluga".