May Highflyer Geometridae

Hydriomena impluviata (Denis & Schiff., 1775)

Description: Wingspan 30-34mm. Adults are variable in colour. Most are greyish brown with a pale central band but some are dark brown with pale antemedian and postmedian lines. There is no apical streak on the forewing.

Similar Species: July & Ruddy Highflyers.

Key Identification Features:

Sets:  male upperside

Flight Period: From the beginning of May to late June.

Status: Widely distributed and commonly encountered on sites around the Lough Neagh area of north Armagh, parts of east Down and more recently Crom Estate, Eshywulligan, Garvary and Legatillida, Fermanagh. It has also been recorded from Rathlin Island, Antrim during the late 1980s. The moth is probably more widespread than records indicate, especially in the west where its foodplant occurs commonly.

Ecology: A variable species with different colour forms. The moth is normally associated with areas where its foodplant, Common Alder Alnus glutinosa, grows. Adults appear at light in small numbers. The larvae can be found from August to October. It overwinters as a pupa.

World Distribution: Across Europe to eastern Siberia.

Bradley & Fletcher number: 1778 Agassiz number: 70.075

Additional information:

UK Moths account


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