The outer cross line on the front wings consists of dark points (often connected) and is well developed.

alvarensis Wahlgren is rather a light form and weakly marked, the lines only distinct at the margins; ab.favillacearia Hbn.

The larva is dungy brown, with a whitish dorsal stripe and some grey markings on the sides.

The species occurs mainly in north central Europe and eastwards to the Urals, predominantly in sandy heathland habitats.

It has been found in open moorland, heathland and peat bogs in many areas in the north of England and Wales, in Scotland and in Ireland.