Plebejus argus (Linnaeus, 1758) - Silver-studded Blue.
Range: the non-tropical Eurasia north to the middle taiga zone.
ssp.: obensis Forster, 1936; range: Ural and the West Siberian Lowland.
A pair making courtship; a female with wing open; a male with wings closed.
A lawn, Akademgorodok [Academy Town], Novosibirsk, West Siberia, Russia. 22nd June 1989. O. Kosterin.