Dociostaurus maroccanus (Thunberg)
Systematic position: Insecta, Hemimetabola, Orthoptera, Acridoidea, Acrididae.
Common name: The Moroccan locust.
Distribution: Mediterranean region, the Middle East and Central Asia to Afghanistan.
Morphology: The adult males are 18.0-28.0 mm in length, the females 23.0-36.0 mm. The body color is basically grey with many irregular darker patches. The thorax bears a pale cross-shape. Forewings are well developed, almost transparent. The nymphs (often termed hoppers) are usually darker, especially if on dark soil.
Life history: This locust has a single annual generation. The eggs are laid in early summer, hatching in the following spring, when green food is abundant. It lives in arid areas, breeding in undisturbed soils, not in arable fields. It needs firm, bare soil for egg laying and the hatching nymphs move to areas of vegetation. A female usually produces 2-3 egg pods, each containing 30-36 eggs. The nymphs resemble wingless adults. They molt five times, growing in size.
Dociostaurus maroccanus is usually solitary, but sometimes its numbers increase, it becomes gregarious and forms large swarms, reaching several thousand nymphs/square meter. The winged adults fly and may cover 60 km during the season, numbers declining as the vegetation is drying up.
Economic importance: This locust has traditionally been considered a serious agricultural threat. Its large numbers, voracious appetite, ability to eat almost all forms of vegetation and propensity to migrate in swarms, have made it a feared pest that may devastate agricultural areas. However, in recent years the swarms have diminished and in some European countries the pest has become rare. Changes in climatic conditions, decreases in spring rainfall and increases of cropland at the expense of grasslands are believed to be the main reasons for this decline.
Management
Horticultural methods: Encouraging the growth of tall grasses and the accumulation of litter. This hampers locust oviposition and reduces the amount of sunlight, and thus heat, required by the nymphs to develop.
Chemical control: Applications of diflubenzuron (an insect growth regulator) in advance of hopper bands moving into cereal fields caused much mortality.
Biological control: Some predatory insects were recorded in Cyprus as feeding on the eggs.
References
Bouaichi A., Coppen, G.D.A. and Jepson, P.C. 1994. Barrier spray treatment with diflubenzuron (ULV) against gregarious hopper bands of the Moroccan locust Dociostaurus maroccanus (Thunberg) (Orthoptera: Acrididae) in N.E. Morocco. Crop Protection 13: 60-72.
Dempster, J. P. 1957. The Population Dynamics of the Moroccan Locust (Dociostaurus maroccanus Thunberg) in Cyprus. Anti-Locust Bulletin 27, 60 pp.
Latchininsky, A.V. 1998. Moroccan locust Dociostaurus maroccanus (Thunberg, 1815): a faunistic rarity or an important economic pest? _Journal of Insect Conservation _ 2: 167-178.
Merton, L.F.H 1959. Studies in the Ecology of the Moroccan locust (Dociostaurus maroccanus Thunberg) in Cyprus. Anti-Locust Bulletin No.34, 123 pp.
Talhouk, A.M. 2002. Insects and Mites Injurious to Crops in Middle Eastern Countries. 2nd Edition. American University of Beirut Press.
Uvarov, B.P. 1933. Ecology of the Moroccan Locust in Iraq and Syria and the Prevention of its Outbreaks. Bulletin of Entomological Research 24: 407-418.,