Wingspan 6-7 mm.
One of the larger of the 'ruficapitella' group of species, all of which feed on oak (Quercus).
The larval mine is a long gallery with linear black frass to begin with, subsequently neatly scattered, and finally more central and irregular. The egg is usually laid on the underside of the leaf
The adults have plain dark brownish forewings with a purplish sheen, with an orange head and creamy collar and eyecaps.
Thought to be only a single extended generation, with larval mines from July to September and adults in May and June.