Description: Wingspan 28-33mm. Adults are variable in colour and mainly darkish brown with a series of narrow wavy lines across the forewings. The females are wingless. Beginning of November to the end of January.

World Distribution: Throughout northern and central Europe.

Irish Distribution: Widely distributed over most counties. The majority of records are from sites in the east where trapping is carried out during the winter. Undoubtedly under recorded in many areas particularly in the west where little mid-winter trapping has been done.

Ecology: Found in a variety of habitats which have trees including urban gardens. Males come frequently to light in reasonable numbers. The wingless females are to be found at night resting on the trunks and the finer branches of trees. The larvae can be found from April to June on a wide variety of trees including birch Betula spp., Blackthorn Prunus spinosa, Hawthorn Crataegus monogyna, Hazel Corylus avellana and willow Salix spp.

Key Identification Features:

• Dark brown with a series of narrow wavy lines across the forewings
• Wingless females
• Flight period

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

iNaturalist: Operophtera brumata at iNaturalist World Species Observations database.