The males of this species have antennae three and a half to four times the length of the forewing and are the longest in the British Lepidoptera. The species has a bronzy-purple forewing with a golden yellow fascia edged in purple. It flies at dusk often in groups.

Damp woodland.

Recorded in 50 (18.5%) of the 270 2km squares of Huntingdonshire.

Last recorded in June 2020

Recorded date range (Adult): 16 May to 08 July