Coenagrion ecornutum (Selys, 1872)
An Asian species ranging from E kazakhstan and Altai to Japan, locally common in S Siberia. It is very close to the European species Coenagrion mercuriale (Charpentier, 1840).
A male
Russia, E Siberia, SE Transbaikalia (Dahuria), SE Chita Province, the SW bank of Lake Barun-Torei at Bulum-Khuduk cordon, reed thickets, 24th June 1995.
O. Kosterin

Fujichrome Provia-100