Chalcalburnus

a genus of fishes of the family Cyprinidae. The body is elongated and of medium size. The posterior section of the keel, located behind the ventral fin, is free of scales. There are several species, inhabiting the basins of the Black, Azov, Caspian, and Aral seas, Van Lake, bodies of water in southern Iran, and the Tigris and Euphrates rivers. The USSR has a single species, Chalcalburnus chalcoides. There are about nine subspecies, which differ in their habits and life histories. For example, the Crimean (C. chalcoides mentoides) and Batumi (C. chalcoides derjugini) subspecies live permanently in fresh water; the Aral (C. chalcoides aralensis) subspecies lives in the Aral Sea; and the Caspian subspecies (C. chalcoides chalcoides) is anadromous. The type subspecies is Chalcalburnus c. chalcoides. The body has a length up to 40 cm and weighs up to 360 g. Spawning takes place in the spring in the Terek and Kura rivers; some individuals enter the Volga and Ural rivers. The females deposit 10,000–50,000 eggs. The diet consists of planktonic crustaceans, insects that have fallen into the water, and small fish. Chalcalburnus is commercially fished and bred.