Over all color silver y with dar ker upperflanks. Fins reddish. Body relatively compressed andelongated. Small head. Dorsal fin located on middle ofback. Origin of anal fin under end of dorsal fin base. Lastunbranched dorsal fin ray thickened into a spine, strongbasally but thinner and flexible distally. Gill rakers shortand only reaching adjacent raker when appressed. Pharyngealteeth hooked at tip with an elongate flat area below,and largest tooth may be strongly serrated. An obviousscaleless keel from pelvic fins to vent. Mouthoblique and subterminal. An axillary pelvic fin processpresent. Gut relatively short with anterior and posteriorloops. Males, females and young may have fine tuberclesover the head. Inhabits upstream, lakes and ponds rich invegetation. Maximum age 7 years and total length 29 cm.Females attain a greater age and size than males. Maturityat 2 years and 8-12 cm total length. Spawning inspring from April to July. Equal sex ratio. Absolute fecundityup to 19,000 eggs of 1.9 mm in diameter. Foodinclude aquatic insects, crustaceans and diatoms.