Wingspan 10 to 13 mm.

Gen det may be required, or good photographs of the moth and the hindwing. 

A species of oak woodland.

A relatively early spring species, the moth is at large during April and May. 

The larva lives in a gall, often that of another hymenopterous insect, feeding internally.

Locally distributed over most of the British Isles. In the Butterfly Conservation's Microlepidoptera Report 2011 this species was classified as local.

Only occasionally recorded in Leicestershire and Rutland, but with pheromone lures becoming popular there may be an increase in records of this species.