Description: Wingspan 24-28mm. Adults have brownish-grey forewings marked with fine white crosslines and a chocolate-coloured blotch at the apex. The hindwings are brownish grey. Not known in N. Ireland. The only dated record for an adult is 25th May 1997. Skinner gives May and June as the flight period in northern regions.

World Distribution: Across northern and central Europe, south to the Balkans, as far east as Tibet.

Irish Distribution: Widely distributed but local. The vast majority of records for this species are of larvae found during the daytime. Adults have only ever been recorded at light on two occasions in N. Ireland - at Carnmore Lough, Fermanagh in May 1997 and Altadavan, Tyrone in 2001. It seems to be well established in the northern counties especially Londonderry where larvae have been recorded from several localities including Banagher, Ballymoney and Aghadowey. Elsewhere, records are somewhat sporadic; other confirmed sites include Garry Bog, Antrim and the Mournes in Down.

Ecology: This species is found on the edges of woodland, bogs, marshes and damp moorland. Adults are apparently attracted to light, but have seldom been found at light in N.Ireland. The two confirmed records were of single individuals that had settled at the edge of the trap rather that inside it. The larvae can be found in July and August on willows Salix spp., hiding during the day between rolled up leaves. It has also been recorded on aspen Populus tremula. It overwinters as a pupa.

Key Identification Features:

• Small size
• Chocolate patch at the apex of the forewing
• White crosslines

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

iNaturalist: Clostera pigra at iNaturalist World Species Observations database.