Anablepidae is a family of fishes which live in brackish and freshwater habitats from southern Mexico to southern South America.[1] There are three genera with sixteen species: the four-eyed fishes (genus Anableps), the onesided livebearers (genus Jenynsia) and the white-eye, Oxyzygonectes dovii. Fish of this family eat mostly insects and other invertebrates.
Fish in the subfamily Oxyzygonectinae are ovoviviparous. The Anablepinae are livebearers. They mate on one side only, right-"handed" males with left-"handed" females and vice versa.[2] The male has specialized anal rays which are greatly elongated and fused into a tube called a gonopodium associated with the sperm duct which he uses as an intromittent organ to deliver sperm to the female.
The family is divided into two subfamilies and three genera:[3]