Wingspan 5-6 mm.
Distributed throughout England and Wales and into the southern half of Scotland, it is more localised in the north, but can be common elsewhere.
The larval foodplant is oak (Quercus), and the mine begins with a narrow gallery following the midrib or a vein, and then becoming a rectangular blotch with frass gathered towards one end.
The adults have coarsely scaled dark brownish wings with a broken creamy fascia, usually as two blotches.
The adult moths are on the wing in June, with mines appearing in August and September.