Bulky head and elongated and cylindr icalcaudal peduncle. Snout short, semi-conical, blunt andabout a quarter of the head length. Gill membranesjoined to each other and free from the isthmus. A largeventral crescentic mouth. Four compressed barbels nearend of the snout which reach almost to the mouth. Gillrakers rod-like. Lower lip continuous with a groove. Fiverows of scutes not interspersed by smaller starry scutes.Small spiracles present. Caudal peduncle semi-conical.Heterocercal caudal fin. Posteriorly positioned pelvicfins. Anadromous and prefers warmer waters, stayingnear the bottom on muddy, sandy or gravel beds whenmigrating. Eurythermal, tolerates salinities up to 22‰.Maximum age 118 years, total length 6 m and weight1340 kg. Maturity at 14-16 years in males and 19-22 infemales. Spawning migration in May-June on muddybeds at 9-17°C. Absolute fecundity up to 2,853,000 eggsof up to 3.4 mm in diameter. Food include polychaetes injuveniles, and other fishes in adults.