Nationally scarce (Na) in bogs, marshes, scrubby moorland and woodland, in the central and western Scottish Highlands. Also appears as an immigrant, mostly in north Scotland and the Scottish islands, the whole of north England, and down the east coast to Essex and Kent, with scattered records inland and as far west as Cornwall, Isle of Man, and Co. Clare in Ireland. In Hampshire and on the Isle of Wight generally a scarce migrant, recorded from time to time in all three vice-counties, however in 2006 a huge influx occurred with in excess of 30 across the county. Wingspan 52-64 mm. Both resident and immigrant forms could be confused with Grey Arches Polia nebulosa
, which flies at the same time and in similar habitats to the resident populations, but this has the orbicular stigma rounded, the reniform stigma less excavated, and hindwing paler with a dark marginal line before the cilia (MBGBI Vol 9). Larva feeds on Bog-myrtle.