Males tr anslucent gr ey to light olive with ablue, sheen on sides and opercle. Iris with a purplesheen. Females with a large, triangular, black blotch onlower flank, behind pectoral fin (gravid spot). Peritoneumblack. Males recognized by anal fin rays modifiedinto an elongate gonopodium for intromittent fertilization.Inhabits clear and weedy streams and ditches, marginsof rivers and lakes and brackish lagoons, over mudor sand bottoms. Maximum age 4 years and total length63 mm in females and 45 mm in males. Survive in salinitiesup to 10‰, temperatures of 0.5-42°C, pH=4.46-10.2and DO levels as low as 0.2 mg/l. Maturity in 2-3months at 16 mm total length. About 17 days after fertilizationfemale gives birth to as many as 428 live fish overa period of about 1 month. Eggs up to 1.8 mm in diameterand embryos about 6-8 mm at birth. Sperm transferredin a spermatophore by several males and can bestored for up to 10 months. Omnivore, food includeaquatic and terrestrial insects, and also filamentous algaeand worms. Females cannibalize larvae.