Wingspan c.17-20 mm.
This is a rare and local species, and in the British Isles is found only in Ireland, inhabiting limestone districts. It was first discovered in Galway, but is largely restricted to the Burren region in Co. Clare, southern Ireland.
Abroad, it occurs in northern Europe, extending east into Russia, and also is known from North America.
The foodplant is mountain everlasting, (Antennaria dioica), the larvae feeding in the stem after overwintering, and causing stunting of the host plant.
Adults fly for a short period around late May.