WikipediaRead full entry
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.