Pests
Aeropus sibiricus (L). - Siberian locust (Siberian grasshopper).
Taxonomic position.
The class Insecta, order Orthoptera, family Acrididae, subfamily Acridinae, tribe Gomphocerini, genus Aeropus. The species has 4 subspecies.Synonyms.
Stenobothrus sibiricus; Gomphocerus sibiricus.Biological group.
Polyphagous insect pests.Morphology and biology.
Coloration of imago is brown, olive, or virescent. Body length, 15.0-20.4mm (male), 19.0-25.9 mm (female). Male antenna widened at apex, with clear flat black club. Female club smaller. Pronotum in anterior part strongly swollen in male, not as swollen in female. Lateral keels of pronotum clear, roundish - concave in anterior part. Posterior margin of pronotum widely rounded. Male elytra slightly longer, female elytra slightly shorter than abdomen, with indistinct light spot in apical quarter. Elytra length 10.0-15.1 mm in male, 7.5-14.7 mm in female. Wings colorless. Piriform swollen fore tibia is the most typical character in males of the Siberian Locust. Hind femora have rounded upper genicular lobes. Hind tibia brownish, yellowish, or reddish. Egg pod small, saccular in shape, with blunt lower and somewhat narrowed upper end, 8-16 mm in length (10-14 mm on average), diameter 5-6 mm in mid-part. The walls are 0.2-0.5 mm in thickness, earthy, formed by foamy secretion with soil particles. An outlet opening is covered with earthen operculum with unsteady junction to lateral walls; some egg pods can have no operculi. Eggs gently bent, whitish-grey, 7-15 in a pod (8-10 on average), 4.2-5.6 mm in length and 1.2-1.5 mm in diameter, arranged in 2-3 rows at an angle 45-70° to lateral walls. Egg pods filled with mild fine-meshed secretion. The thickness of secretion above eggs does not exceed 1-2 mm. Larvae have 4 instars.Distribution.
The species is found almost throughout Siberia, in the north of the European part of Russia, northern half of Kazakhstan, mountains of the Caucasus, Kazakhstan, and Central Asia, and mountains of southern Europe, Mongolia, northeastern China, and Tibet.Ecology.
The Siberian Locust is an ecologically plastic species capable of changing behavior and morphology as a result of population density and ecology. As a whole it prefers steppe localities with gramineous vegetation, particularly mesophytic localities on plains, and xerophytic in mountainous regions. The species frequently populates trampled pastures and couch-grass fallow lands. At the period of pod laying, the insects prefer dry, sun lit, gently turf-covered sites of soil. The greatest concentration of pods in Siberia is observed on bare plots with bare eroded or trampled soil surface with a vegetative covering of 40-60% per square meter. The depth of holes is 15-25 mm. Sometimes the pods lie on soil surfaces thinly covered with litter. The species has early-vernal phenology; larvae hatch in southern locales at the end of April; in northern locales, in early May. Larval development passes 4 stages within 24-28 days. Copulation begins 5-10 days after first flying; pod laying starts 5-10 days later and lasts for about 4 weeks. Pod density can sometimes reach 1,000 pods/sq.m. Imago starts to die in the second half of July.Economic significance.
One of the most serious pests of agriculture in the eastern regions of the European part of the former USSR, the southern forest, forest-steppe and steppe zones of Kazakhstan and of Siberia. The larvae and adults severely damage summer sowings of wheat, rye, oat, barley, and to a lesser extent winter rye, corn, panicum, mogar, buckwheat, tobacco, potato, cabbage, mustard, hemp, flax, and other agricultural crops, and also pastures and hays. Mass outbreaks are repeatedly recorded in the literature, especially in the eastern regions. The number of Siberian Locust has notably increased in Northern Kazakhstan, and in Western and Eastern Siberia during recent years, which may be attributed to a decrease in chemical control following independence. Mass outbreaks of the Siberian Locust threaten grain crops, which are most vulnerable to damage during the initial phases of their development.Reference citations:
Bei-Bienko G.Ya. 1932. A manual of locust survey. Leningrad: Upravlenie Sluzhby ucheta Gos. OBV Narkozema SSSR. 159 pp. (in Russian).Bei-Bienko G.Ya., Mishchenko L.L. 1951. Locusts of the fauna of the USSR and adjacent countries. Keys to Fauna of USSR, N38, parts I & II. Moscow & Leningrad: AN SSSR. 668 pp. (in Russian).
Lachininskii A.V., Sergeev M.G., Chil'debaev M.K., Chernyakhovsky M.E., Lockwood J.A., Kambulin V.E., Gapparov F.A. 2002. Locusts of Kazakhstan, Central Asia and adjacent territories. Laramie: Association for Applied Akridology International, University of Wyoming. 387 pp. (in Russian).
Sergeev M.G. 1986. Regularities in distribution of orthopterous insects of Northern Asia. Novosibirsk: Nauka. 238 pp. (in Russian).
Sergeev M.G., Kopaneva L.M., Rubtsov I.A., Antipanova E.M., Bugrov A.G., Vysotskaya L.V., Ivanova I.V., Kazakova I.G., Karelina R.I., Pshenitsna L.V., Sobolev N.N., Chogsomzhav L. 1995. Siberian Locust (Aeropus sibiricus L.). Novosibirsk: Nauka. 176 pp. (in Russian).