Back br ownish to yellowish or olive-green,flanks silvery-white and belly white with silvery tints.Head, body and dorsal fin covered with small, distinctiveblack spots. Upper flank scales outlined with dark pigments.Eye orange above or mostly silvery. Lower finsorange to yellow at the base and blackish distally. Lowerrays of the caudal fin with a slight orange-yellow tint.Peritoneum dark brown to black. Body compressed, headsmall and pointed. A spectacularly high and strong lastunbranched dorsal fin ray with 23-31 denticles. Predorsalarea compressed, lacking scales except near the occiput.Pelvic axillary scale present. Males bear tubercles onflank scales, head, dorsal and anal fins. Gut elongatedwith anterior and posterior loops. Maximum age 10 yearsand total length 53 cm. Females longer and heavier thanmales. Stenohaline, but widely distributed in freshwaterrivers. Spawning in May-June. Maturity at 2-3 years. Sexratio 1male:1.5females. Absolute fecundity up to 18,240eggs with a diameter of up to 2.1 mm. Food include detritus,diatoms, algae and benthic invertebrates.