Ship sturgeon with scientific name Acipenser nudiventris has a stretchy body and conical snout. The main features of this sturgeon are its large first back bone plate and the lack of a cut in the middle part of the lower lip. Its mustaches have ciliate bifurcations. A part between the rows of plates is smooth and bare and without bony bumps. It mainly resides in the southern part of the Caspian Sea and in the past has had large migrations to Sefidrud (White River) for spawning. Its average weight is 20kg and its maximum is reported to be 43kg.
In nature, ship sturgeon males generally mature at age 9 to 13 and females at the age 13 to 16 in the Caspian Sea. In breeding environments, males and females mature at age 7 and 8 to 10, respectively, and caviar amounts to 12 to 15 percent of their body weight.
At different stages of growth, their main food is gammarus (Roosh), various types of bloodworms, Atherina, substrate molluscs and crustaceans and sometimes the kilka fish, its catch has taken the fifth place among the Caspian sturgeons. IUCN has declared their reserves as endangered in the Caspian Sea.