Small Argent & Sable Geometridae

Epirrhoe tristata (Linnaeus, 1758)

Description: Wingspan 24-26mm. A small, distinctive moth. The basal colour of the forewings is white with a light brown central band. The outer margins of all wings are suffused with black with a small faint line.

Similar Species: This species resembles the larger Argent & Sable Rheumaptera hasta hasta, which has a greater area of white on the forewings and the band greatly reduced, often to a few small patches.

Key Identification Features:

Sets:  male upperside

Flight Period: Mid-June to early July.

Status: Scarce and local, reported in recent times only from the Slieve Gullion area of south Armagh. Previously recorded from Armagh City back in the late 1960s. It has not been rediscovered from any of its former haunts at Tollymore Forest Park,Down, Knockagh Antrim, and the Enniskillen area, Fermanagh, where it was taken back in the mid 20th century. There may be other small isolated populations in the south Armagh area that have remained undetected due to the lack of fieldwork in this area for many years.

Ecology: A small pretty species associated mainly with upland heaths and limestone hills. Adults will often fly in afternoon sunshine as well as at dusk. The larvae can be found in July and August on Heath Bedstraw Galium saxatile. It overwinters as a pupa.

Bradley & Fletcher number: 1737 Agassiz number: 70.060

Additional information:

UK Moths account


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