Rare on dry, sandy heathland in the Brecks and elsewhere in East Anglia. Unlikely to be recorded in Hampshire or on the Isle of Wight. Wingspan 13-18 mm. Distinguished by the dark grey-brown general coloration of the forewing and the conspicuous, subtriangular or subquadrate black-brown patch representing the median fascia in the discocellular area [Bradley]. Larva feeds within bark of European Larch, forming galls, over-wintering twice.