Last modified: May 5, 2021, 10:37 a.m.
A rather common species in Belgium, although populations have declined because of the Dutch elm disease; during the last decennia the species seems to have recovered.
Head ochreous to dark brown; forewing ground colour dark brown; white pattern consisting of a very inconspicuous and small basal streak, sometimes absent; two transversal bands; one costal and one dorsal striae, often touching the middle of the wing to form a third band; another costal stria in the apical region.
A long, elongated tentiform mine on the underside of a leaf, between two secondary veins. The mine usually starts at the main vein and extends to the leaf margin. The last instar applies much spinning inside the mine so that it contracts into a tube. On the underside several longitudinal folds, close to each other, whitish green in the beginning, brownish in the last stages. The frass is concentrated in a corner of the mine.
See also gracillariidae.net and bladmineerders.be.
A tough, brownish cocoon attached to the floor of the mine.
The species hibernates in the pupal stage, between leaf litter on the ground. After emergence of the adult, the pupal skin protrudes through the mine.
Two generations a year: May and August.