Anagrus atomus (L.)
In vineyards and the surrounding vegetation A. aromus may co-occur with the very similar Atomus parvus Soyka, and some of the data may pertain to the latter species. In addition, two species-groups were recently proposed for taxa within the entity known as Anagrus atomus.
Distribution: Europe, Asia, North America.
Morphology: Body about 0.2 mm in length, mostly dark yellow, head black, antennae as long as body, dark yellow along most of their length, distal segments dark. Wings very narrow, with long fringes.
Life history: An egg parasitoid of many leafhoppers on various host plants, in Europe especially on vines. Its parasitization rates are affected by the foliar pubescence on grape cultivars, especially by the erect hairs on the veins. At 24ºC a generation can be completed in 2 weeks and about 260 day degrees are required to complete a generation. At that temperature fecundity is about 30 eggs/female. In autumn an increasing part of the population develops slower, their larvae being darker than the normally-developing larvae. This slower development, and thus later emergence, enables the parasitoid to emerge when host eggs are available on evergreen host plants. Two entomopathogenic fungi that attack leafhoppers had no effect on A. atomus, but reduced its rates of parasitism on these hosts.
Economic importance: Anagrus atomus is an important enemy of several pestiferous leafhoppers, whose parasitization rates may at times come to 70% or more. In Turkey it effectively controlled leafhoppers that infested corn (maize), parasitization rates at times being >90%; similar controlling rates of another leafhopper were reported from Switzerland. In Europe A. atomus is mass-reared and sold as a biopesticide, usually suppled as pupae, and placed around leafhoppers infestations. .
Agboka K., Tounou, A.K.., Al-Moaalem, R., Poehlıng, H.-M., Raupach, K. and Borgemeister, C. 2004. Life-table study of Anagrus atomus, an egg parasitoid of the green leafhopper Empoasca decipiens, at four different temperatures. BioControl 49: 261–275.
Cerutti F., Baumgärtner, J. and Delucchi, V. 1990. Ricerche sull’ecosistema “vigneto” nel Ticino : III. biologia e fattori di mortalità di Empoasca vitis Goethe (Homoptera, Cicadellidae, Typhlocybinae). Mitteilungen der Schweizerischen Entomologischen Gesellschaft 63: 43-54.
Chiappini E. 1989. Review of the European species of the genus Anagrus (Hymenoptera: Mymaridae). Bolletino Zoologica Agraria Bachicoltura Serie II, 21: 85–119.
Mutlu, Ç. and Sertkaya, E. 2015. The parasitization rates on some harmful leafhoppers on maize of the egg parasitoid, Anagrus atomus (Hymenoptera: Mymaridae). Türkiye Biyolojik Mücadele Dergisi 6: 25-40. (In Turkish with an English abstract.
Nugnes, F., Bernardo, U. and Viggiani, G. 2017. An integrative approach to species discrimination in the Anagrus atomus group sensu stricto (Hymenoptera: Mymaridae), with a description of a new species. Systematics and Biodiversity 15: 582-599.
Pavan, F. and Picotti, P. 2009. Influence of grapevine cultivars on the leafhopper Empoasca vitis and its egg parasitoids. BioControl 54: 55-63.
Tounou, A.-K. (and 6 co-authors). 2003. Evaluation of the entomopathogenic fungi Metarhizium anisopliae and Paecilomyces fumosoroseus (Deuteromycotina: Hyphomycetes) for control of the green leafhopper Empoasca decipiens (Homoptera: Cicadellida) and potential side effects on the egg parastoid Anagrus atomus (Hymenoptera: Mymaridae). Biocontrol Science and Technology 13: 715–728.
Triapitsyn, S.V. 1998. Anagrus (Hymenoptera: Mymaridae) egg parasitoids of Erythroneura spp. and other leafhoppers (Homoptera: Cicadellidae) in North American vineyards and orchards: A taxonomic review. Transactions of the American Entomological Society 124: 77-112.
Zanolli, P.. Martini, M., Mazzon, L. and Pavan, F. 2016. Morphological and molecular iIdentification of Anagrus ‘atomus’ group (Hymenoptera: Mymaridae) individuals from different geographic areas and plant hosts in Europe. Journal of Insect Science 16: 1–14.
Zanolli, P., Nelope, P., Van, F. and Ances, O. 2013. Occurrence of different development time patterns induced by photoperiod in Anagrus atomus (Hymenoptera: Mymaridae}, an egg parasitoid of Empoasca vitis Homoptera Cicadellidae. Physiological Entomology 38: 269-278.