Gambusia affinisWestern Mosquitofish
authority not recorded
Max length
40mm SL1.6in SL
For many years G. affinis was thought to be the same species as the Eastern Mosquitofish, G. holbrooki, but has since been given distinct species status. They can be distinguished by several means. In G. holbrooki the leading ray of the males' gonopodium has a serrated edge, theusually has 7 rays and males also generally have a higher degree of dark spotting on the body than G. affinis males. Male G. affinis also lack the serrated leading ray of the gonopodium and this species usually has o...