Grey Scalloped Bar Geometridae

Dyscia fagaria (Thunberg, 1784)

Description: Wingspan 31-40mm. Adults are variable in size and colour. The typical form tends to be light greyish brown with two darker cross-lines and a small dark discal spot near the costa. Paler forms are also common among populations.

Key Identification Features:

Sets:  male upperside

Flight Period: Mid-May to mid-August.

Status: Widespread and frequently encountered where it occurs, especially in Fermanagh, east Tyrone and north Antrim. In Down there are no recent records apart from an old record dating back to 1903 from the Newcastle area.

Ecology: A species commonly associated with upland and lowland heaths and bogs. Adults are occasionally seen at light but usually in small numbers. According to Skinner adults can be found after dark resting on Heather Calluna vulgaris. The larvae can be found from late September through to April of the following year on Heather and Cross-leaved Heath Erica tetralix. It overwinters as a larva.

World Distribution: Throughout northern and central Europe as far east as Russia.

Bradley & Fletcher number: 1969 Agassiz number: 70.292

Additional information:

UK Moths account


 Thompson, R. S. & Nelson, B., 2003 (Oct 2). [In] The Butterflies and Moths of Northern Ireland