The outer part of the rounded, straw-white forewing darkens towards the trailing corner and this is diagnostic. On some individuals, the darkening is evident as a dark brown band, but even lighter specimens have at least two small dark marks. The dots around the border of both the forewing and hindwing are sometimes absent.
Pupates in plant debris.
Woodland, hedgerows, gardens, marshes and fens.
Recorded in 133 (49.3%) of the 270 2km squares of Huntingdonshire.
Last recorded in September 2020
Recorded date range (Adult): 28 May to 14 October