The wingspan is 14–17 mm. The moth flies from May to July depending on the location.
The larvae feed on Quercus, and supposedly also Prunus and Salix. Full-grown larvae live in a black pistol case of about 8 mm, with a mouth angle of about 90°. The case is covered by a silken mantle that hangs from its rear end, and almost covers the case. The larvae mine the leaf from the underside, making many, unusually small fleckmines. Full-grown larvae can be found in early June.