The life history of the imagines of Glyptotendipes paripes is described. The emergence has a peak of 45-120 minutes after sunset at a duration of civil twilight of 24 minutes. The newly emerged midges fly with the wind to the shore; the females normally mate with older males during this flight, and in some cases also with new males at least after arriving at the shore. Matings also occur during and shortly after a swarm-like flight which takes place at dawn. During the night and the day the midges stay close to the shore of the lake. At sunset the animals return to the lake where the females deposit the eggs 30-90 minutes after sunset. The "empty" females and the males return to the shore flying with the wind which enables the males to intercept the newly emerged females on the flight to the shore. The copulation is effected by means of spermatophores.