East chestnut gall wasps Dryocosmus kuriphilus Yasumatsu, 1951 (Hymenoptera, Cynipidae) - new invader in the forests of the North Caucasus.
Results of the first studies of a new invasive pest of the sweet chestnut, the eastern chestnut gall wasp Dryocosmus kuriphilus, are presented. For the first time, this invader was discovered within the territory of Russia in 2016. Data on its distribution and some characteristics of the damage are given. Several types of galls are formed as a result of the larvae feeding. The level of occupancy of chestnut by the pest is shown.