Anagrus

Several species of Anagrus have been used in biological control projects and Anagrus species are generally important as naturally-occurring pest control agents in several agroecosystems, notably in rice fields where they suppress leafhopper and planthopper populations (for example, Claridge et al., 1999), and in viticulture. The biology of Anagrus optabilis, an egg parasitoid of delphacid planthoppers, is detailed by Sahad (1984). A few species are specialist parasitoids of plant-feeding lace bugs (Heteroptera: Tingidae), and their potential as biocontrol agents of these pests has been assessed (for example, Balsdon et al, 1996). Laboratory rearing methods are described by Chandra and Dyck (1988). Several studies have also been carried out on superparasitism and mutual interference (Chantarasaard et al., 1984; Cronin and Strong, 1993; Zhu et al., 1990).Important SpeciesA. armatus is a common species, described originally from North America, but now very widespread and also occurring in South America and the Australo-Oriental and Oceanic regions. De Santis et al., 1988 reviewed the taxonomy and biolgy, and Beers and Elsner (1988) studied its effects on apple leaf hoppers in Washington State, USA.A. atomus is a very common, essentially Holarctic species (though recently recorded additionally from Argentina; Triapitsyn, 1999). It has a very broad host range, but is most commonly associated with leafhoppers important to viticulture (for example, Arboridia adanae, Emposasca vitis; Cerutti et al., 1989) both in Europe and the USA. (Triapitsyn, 1998). Other investigations have concentrated on its biocontrol potential in glasshouses, particularly against pests of tomato (Jacobson et al., 1996).A. avaleae is another common Holarctic species with a host range encompassing several Typholocyba species (Chiappini and Triapitsyn, 1999).A. breviphragma currently has a rather curious Palaearctic-Neotropical distribution, and could therefore be expected to be found in the Nearctic. It has a broad host range, with its hosts associated with graminaceous plants including both wild and cultivated cereals.A. cicadulinae attacks C. mbila in Southern Africa, a cicadellid vector of maize streak virus.A. empoascae is a New World species also occurring in India. It is associated with several cicadellid species, mostly in the genus Empoasca, on a variety of host plants belonging to the Euphorbiaceae, Fabaceae, Malvaceae and Solanaceae, including several cultivated species.A. epos is a common North American species attacking eggs of Cicadellidae, mostly in the genus Erythroneura and associated with horticulture.A. erythroneurae is another common North American species attacking eggs of Cicadellidae, mostly in the genera Dikrella, Erythroneura and Typhlocyba, and associated with horticulture.A. flaveolus is an extremely widespread, common and polyphagous species attacking both cicadellid and delphacid hoppers, especially those associated with rice, including the brown planthopper, Nilaparvata lugens. Rearing methods for this species have been described by Chandra and Dyck (1988).A. frequens, described from Australia, was introduced into Hawaii early this century against both the corn (maize) planthopper, Peregrinus maidis, and the sugarcane leafhopper, Perkinsiella saccharicida, against both of which it established.A. nigriventris, described from the USA, was introduced into mainland Australia and Tasmania (in the latter case from New Zealand) against the apple leafhopper, Edwardsiana crataegi. It has been treated under the name Anagrus giraulti in some published literature (for example, Meyerdirk and Moratorio, 1987).A. nilaparvatae is an important parasitoid of the eggs of several delphacid planthoppers attacking rice in China. Several studies have been published on this species (for example, Zhu et al., 1990, 1991).A. optabilis, described from Australia, is now widely distributed in the Oriental region and some Pacific islands where it is commonly reared from eggs of sugarcane and rice planthoppers. It was introduced into Hawaii in 1905 against the sugarcane pest Perkinsiella saccharicida, where it established and became common (Clausen, 1978). Its biology was described in detail by Sahad (1984).A. perforator is a widespread parasitoid of several delphacid planthoppers associated with rice, sugarcane and many other host plants. It has been widely introduced into much of its current distribution.A. ustulatus is a common, originally European species, attacking typhlocibine Cicadellidae associated with Rosaceae.