Status: - Widespread and common on the western side of Scotland, most of Wales and from the Isle of Wight westwards, elsewhere locally restricted.
Habitat: - Fast flowing peaty runnels to small rivers where slower flow rates allow the build up of silt, small stones or fine detritus suitable for the sedentary larva to bury itself.
Flight period: - Early June to the end of August.
General: - The waters it is associated with are normally acidic, typically less than one or two meters wide and often deeply cut into the surrounding terrain. Males can be seen cruising slowly up and down suitable breeding habitat and are not easily disturbed.
When they meet another male they usually turn away but occasionally a really aggressive attack ensues. Both sexes can be found hunting for food well away from breeding sites usually over heathland. They have been seen in woodland and over still water.
Copulation takes place either in a tree or among the heather and ferns. Egg-laying females hover vertically above suitable shallows and, reminiscent of a road repairers pneumatic dill, drives her ovipositor into the substrate, undisturbed she can keep this up for up to 15 minutes.
The ovipositor of older females is often seen to have suffered significant erosion.