Last modified: Dec. 8, 2022, 6:48 p.m.
A rare species throughout Belgium. This species is often confused with C. flavipennella which is more common.
The forewings are ochreous till brownish ochreous, often with a little orange shine. They are not greyish and haven't also a costal area which is lighter coloured. Rather often, and not so obvious to see, is that the base of the wing and also the apex are a little darker.
Wingspan is about 10–12 mm.
The antennae are alternately ochreous till darker brown and white ringed.
At first the larva makes a pistol case. After hibernation it makes a total different case completely made of silk.
The case is 7 mm long and the mouth angle is 45°.
See also bladmineerders.be.
At first the larva makes a very little corridor with a little frass.
The young larva makes a very small mine. Caterpillars are fully grown in June then they pupate.
The adults fly in June and July.
The larva feeds from a rather straight, ochreous case on Quercus.