Description: Wingspan 40-44 mm. Forewings are pale to dark grey with darker grey antemedian and post median lines. These are not always clearly defined. The stigmata are pale grey outlined with black. The subterminal line is white but obscured for most of its length by a darker suffusion in some individuals. Hindwings white with black veining. Mid-May to late July.

World Distribution: Throughout western Europe from Spain to the Arctic Circle.

Irish Distribution: Common and generally distributed in a line west from Belfast through north Armagh to south Fermanagh. There have been no recent records from northern counties.

Ecology: A species found in woodland habitats where poplars are present. Adults are attracted to light and flowers. It rests during the daytime on the trunks of various trees. The larvae feed from July until September on poplar Populus spp. and possibly willow Salix spp. It overwinters as a pupa.

Key Identification Features:

• Dark grey mottled appearance of the forewings
• Pale stigmata normally outlined in black
• White hindwings with dark veining

Distribution Map from NBN: Acronicta megacephala at National Biodiversity Network mapping facility, data for UK.

iNaturalist: Acronicta megacephala at iNaturalist World Species Observations database.