The White-tailed Skimmer (Orthetrum albistylum) is a dragonfly species, which occurs from central and south Europe to China and Japan.
The adult male White-tailed Skimmer superficially resembles the Black-tailed Skimmer (Orthetrum cancellatum) but the abdomen is noticeably slimmer and usually, but not invariably, has white appendages.
Females also look much the same as the female Black-tailed Skimmer but the black bands along the top of the abdomen are more curved and Segment 10 is also white like the appendages.
Both sexes have pale bands on the sides of the thorax.
Males before maturing appear similar to females.

Lake Kerkini, Greece, 30 July 2017