The outbreak of harlequin ladybird Harmonia axyridis (Pallas, 1773) (Coleoptera, Coccinellidae) in the Caucasus and possible sources of invasion

Abstract

Recently, the invasive harlequin ladybird (Harmonia axyridis), which has been speading rapidly throughout the world, has naturalized in the Caucasus. According to our data, the range of its outbreak covers the Black Sea coast of Krasnodar krai and part of the Abkhazian coast and also the southern and northern foothills of the Greater Caucasus. Both light (form succinea) and dark (form spectabilis) specimens are detected to the north of the mountain ridge, but there were no dark specimens among 220 beetles collected to the south of the mountain ridge. The drastic difference between populations indicates their different origin. Probably, the Transcaucasian population of beetles appeared as a result of their mass release in Georgia in the 1980s, and the Caucasian population appeared as a result of later releases of beetles in Krasnodar krai or of spontaneous expansion of the European range. The introduction of a new alien predator can affect the state of the Caucasian entomofauna. Harlequin ladybirds pose a threat to local populations of ladybirds as well as to butterflies which develop on leaves. In addition, H. axyridis can cause injury to fruits and grapes, posing a threat to fruit and wine production.