Last modified: Jan. 5, 2020, 4:45 p.m.
A rather common species in Belgium and is found more frequently after 2004.
The full-grown larva of this species has a blackish brown pistol case of about 7 mm long and, with a mouth angle of circa 70°, standing almost perpendicular to the leaf.
See also bladmineerders.be.
In springtime, the caterpillar lives in the buds. Later on, it makes skeletal food patterns on the leaves. Pupation takes place on a twig or upon a leaf.
The adults are on the wing mostly in July.
This mono-phage species lives on Salix but, since this plant grows throughout the whole of Belgium, the cases can also be found everywhere.