Description: Wingspan 34-40 mm. Forewings narrow and normally dark brown, slightly paler in the basal region. Antemedian line blackish brown and convex; postmedian line paler, weakly defined towards the costa. Stigmata paler than base colour and finely outlined in black. The subbasal line is normally reduced to a couple of black dots. There are three black parallel streaks at the apex of the forewing. Hindwings pale fuscous with a darker terminal border. Beginning of June tp mid-August.

World Distribution: Eurasiatic; common and widespread throughout western Europe

Irish Distribution: Common and widespread across southern counties, scarcer further north in small scattered populations. It has not been recorded from Rathlin Island.

Ecology: Baynes remarked that this species was more common in Ireland than the Spectacle A. triplasiaThis would appear not to be the case in the north. It seems to occur on a variety of habitats and adults have been frequently taken in suburban gardens, especially in the Greater Belfast area. Adults come to light in small numbers and also visit flowers after dusk. The larvae feed during August and September on Common Nettle Urtica dioica. It overwinters as a pupa.

Key Identification Features:

• Colouration of adult
• Stigmata which are outlined in black Three parallel streaks at the apex of the wing

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

iNaturalist: Abrostola trigemina at iNaturalist World Species Observations database.