Body dar ker dor sally and upper flankmuch darker than the lower one. Mid-flank darkpigmentation forms a weak stripe. Fins mostly immaculatewith traces of melanophores. Pectoral, ventral andanal fin bases yellowish. Peritoneum silvery with numerousscattered melanophores. Body elongate and somewhatcompressed. Straight upper profile and a lower gentlearch. Snout short and pointed. Mouth oblique andslightly superior. Mouth tip on a level with the upper halfof the eye. Anal fin origin posterior to dorsal fin insertion.Lateral line decurved on belly and on midline onposterior half of caudal peduncle. Pelvic axillary scalepresent. The naked ventral keel flanked for six scalerows anterior to anal fin. Gut elongate and S-shape.Small tubercles on sides and top of head, dentaries, caudalpeduncle scales, and upper pectoral fin rays of maturemale. Males with wider interorbital, deeper caudalpeduncle, and longer fins. Maximum total length 135mm and weight 24 g. First maturity at 1-2 years and 88mm. Spawning in June-August, at 15ºC or higher. Absolutefecundity 1,400 eggs of 1 mm in diameter. Food includephytoplankton, insects and aquatic plants.