Family GERRIDAE Leach, 1815 ‑ water striders, pond skaters
N.M. Andersen
The family includes 63 genera and about 530 species, distributed worldwide. All species are predators of insects fallen on the water surface. Water striders live in a variety of aquatic habitats, on stagnant water, usually avoiding surfaces with extensive plant coverage, on flowing water including torrents, in coastal marine habitats, and even on the open ocean (Halobates species, sea skaters). A few species are secondarily adapted to humid terrestrial (hygropetric) habitats (Eotrechus, Onychotrechus). Most species overwinter as adults. The eggs are usually deposited superficially on floating or submerged plants, rarely inserted in plant tissue (Rhagadotarsus). There are always five larval instars. Most species are wing-dimorphic and long winged adults of some species break off their own wings.
World catalogue: Lethierry & Severin, 1896 (outdated). Palaearctic catalogue: Andersen, 1995h. Monographs: Andersen, 1982a (general account); Hungerford & Matsuda, 1960a (key); Matsuda, 1960 (morphology, classification). Faunal reviews: China ‑ Hoffmann, 1941; Chen & Andersen, 1993; France ‑ Poisson, 1957a; Great Britain ‑ Savage, 1989; Ireland - Savage, 1989; Italy ‑ Servadei, 1967; Tamanini, 1979; Japan ‑ Miyamoto, 1958, 1961a; North Africa ‑ Poisson, 1941b, 1965b; Northwest Europe ‑ Andersen, 1994; the former Soviet Union ‑ Kanyukova, 1982a; W Palaearctic ‑ Stichel, 1955‑1956. Biology: Cobben, 1968a, 1978; J.T. Polhemus & Chapman, 1979; Southwood & Leston, 1959; Spence & Andersen, 1994.