Locusta migratoria Linnaeus, 1758

Sergeev, M. G. & Dubatolov, V. V., 2022, New data on Orthoptera distribution in the southern part of the Russian Far East, Far Eastern Entomologist 450, pp. 15-20 : 17-18

Locusta migratoria Linnaeus, 1758

MATERIAL. Khabarovsky Krai: Bolshekhekhtsirsky Nature Reserve, Ussuri River,

downstream Chirki River mouth, lower sandy flood-plain with scarce vegetation, 12.VII

2018, 1♂ larva; the same locality and habitat, 20.VII 2018, several larvae observed ( V.

Dubatolov)

REMARKS. The species was commonly mentioned for the southern part of the Russian

Far East as the accidental one (Bey-Bienko, 1966). The dense population of the migratory locust was found for the first time in the southern part of the Khabarovsky krai.

DISTRIBUTION. Russian Far East: Khabarovsky krai (new record), southern part of Primorsky krai (Mistshenko, 1972; Storozhenko, 1986, 2018), Moneron Island (Storozhenko,

1986), Kunashir Island (Bey-Bienko, 1966; Kryvolutskaja, 1973; Storozhenko, 1985). The migratory locust is most widely distributed species. Its range includes almost all Eurasia

(except the North), Africa, Australia and many islands (Ma et al., 2012; Sergeev, 2017). The nominotypical subspecies is chiefly distributed in the extra-tropical regions. In China, the migratory locust occurs over almost all territory including its north-eastern regions (Zheng &

Xia, 1998). Importantly, the gregarious form of the species was mentioned from Korea and

NE China as well (Rehn, 1902; Ikonnikov, 1913; Bey-Bienko, 1930). Furthermore, the outbreaks of the migratory locust were observed in 2009 in the southern part of Heilongjiang province of China (Tu et al., 2020).

ECOLOGY. The migratory locust is one of the most important pests in a number of countries. Its populations are usually associated with reed beds, but in Tuva, its dense population was observed over the Achnatherum grasslands (Sergeev, 2017). The newly discovered population was found in the local lower sandy flood-plain. It included hoppers of different ages. One could suppose that the population was stable, however, this part of the river valley was overflowed in the end of July and August of 2018. The similar situations were observed in 2019–2021. As a result, some attempts to find the species again in the same location were unsuccessful. Nevertheless, one may hypothesize that some stable populations of the migratory locust occur across local reed beds (including the adjacent areas of NE China). The alternative idea was suggested by Tu and co-authors (Tu et al., 2020).

They supposed that the recent outbreaks of the migratory locust in Heilongjiang were resulted from long north-eastward migrations of Locusta migratoria migratorioides (Reiche et Fairmaire, 1849) = L. migratoria manilensis (Meyen, 1835) . In any case, as we know the trends of climatic changes, particularly warming, are very notable, that means both the general number of local populations of the migratory locust and its common abundance can increase in the near future. This may result in some serious problems for the plant protection systems in the southern parts of the Russian Far East and NE China (cf. Tu et al., 2020).

Tribe Trilophidiini