Last modified: April 8, 2021, 8:45 p.m.
An uncommon species in Belgium.
See also bladmineerders.be
The mine starts in the petiole, or bark or twig and ends with an excision very close to the leaf-base of the leaf. The oval case is portable and the larva descending in it to the ground where it's attached to detritus. Pupation in the case.
The adults fly in one generation a year: during May and early June. The adults can be seen flying in numbers round the lower branches of the food plant and in the surrounding undergrowth.
The larva lives on Quercus.