The Common Hawker (or Moorland Hawker) is a large slender dragonfly with a 7-8 cm long brown body.
The male has a black abdomen with paired blue and yellow spots on each abdominal segment, and narrow stripes along the dorsal surface of the thorax (chest).
In the female, the abdomen is brown with yellow or sometimes green or blue spots.
The wings of both sexes display a yellow costa (the major vein running along the leading edge of the wings).
The back of each eye shows a distinctive yellow spot.
This species lacks the green thorax stripes of the Southern Hawker (Aeshna cyanea; in Dutch: Blauwe Glazenmaker).

Recent study (2015) by Rassim Khelifa of the University of Zurich shows that female Common Hawkers use an extreme tactic to get rid of unwanted suitors. When she is being pursued by a male that she doesn’t want to mate with, she’ll suddenly plunge to the ground and fake her own death. When he finally flies away, so does she.
They are vulnerable to harassment when they lay their eggs since, unlike some other dragonflies, they aren’t guarded by their male mates. Copulating again with another male could damage their reproductive tract. Females may only behave in this way if male harassment is intense. 27 out of 31 female Common Hawkers that were observed during the study did this.

Lac de Fontaine, Haute-Savoie, France, 1 August 2016