Last modified: April 6, 2022, 12:09 p.m.
A rather common species throughout Belgium
Head white with some scattered ochreous scales; forewing ground colour golden ochreous with an unmistakable pattern of white scales; a whitish patch in the basal ochreous field which is sharply edged with brown scales, a large white area in the middle of the wing; four costal and two dorsal striae, all situated very closely to the apical area; a small but conspicuous black dot in the apical area, from which a dark grey hook in the apical cilia arises.
A large (ca. 20 mm), semi-circular or oval, tentiform mine on the underside of a leaf, mostly close to the leaf basis. Mostly much contorted. Underside of the mine with rather many, very fine longitudinal folds. The black frass is concentrated in one corner of the mine.
See also gracillariidae.net and bladmineerders.be.
The species hibernates in the pupal stage, among leaf litter on the ground. After emergence of the adult, the pupal skin protrudes from the mine.
Two generations a year: end of April till the beginning of June and in August.
The species is monophagous on Quercus, in Belgium mainly found on Quercus robur, but also recorded from Q. petraea and Q. pubescens.