Family PLEIDAE Fieber, 1851 - pygmy backswimmers
The family contains 3 genera and about 36 species, with a worldwide distribution, but much more prevalent in the tropics. All species are thought to be predaceous on arthropods, and some have been considered for mosquito control. Species are usually found in lentic habitats, but occasionally in lotic habitats. They overwinter as adults. Eggs are inserted in aquatic plants. Many species are wing-dimorphic; the flightless forms have reduced hind wings and a slightly different morphology, which has led to confusion at the species-group level.
Monographs: Esaki & China, 1928. Palaearctic catalogue: J.T. Polhemus, 1995h. Biology: Wefelscheid, 1912.