Last modified: April 10, 2021, 1:44 p.m.
A widespread but local and fairly common species in Belgium.
Native
A semi-circular or oval tentiform mine on the underside of a leaf. At first the mine has a yellowish tinge, sometimes with a pink, or even reddish, hue, but after a while it colours dark brown till even blackish. The underside is flat, without any longitudinal folds. The black frass is concentrated in a corner of the mine.
See also gracillariidae.net and bladmineerders.be.
A flimsy cocoon in the opposite corner than the one where the frass is stored. Pupal skin very dark brown or black.
The species hibernates in the pupal stage. After emergence of the adult, the pupal skin protrudes through the mine.
Two generations a year: April–May and August–September.
The species is monophagous on Populus tremula, especially the saplings.