This species is easily confused with other Bactra species. It can be distinguished from B.furfurana by the crescent-shaped discocellular mark and the absence of a basal patch on the forewing; unicolourous specimens can only be separated by examination of the genitalia.
Recorded in 32 (11.9%) of the 270 2km squares of Huntingdonshire.
Last recorded in August 2019
Recorded date range (Adult): 14 May to 17 September