Head white; forewing ground colour silvery white, a little darker with yellowish hue in the apical area; five ochreous to brown costal striae of which the second one is prolonged to the dorsum, thus forming a narrow transversal band; a black spot in the apical area from which two dark brown hooks depart into the cilia, forming a horizontal "V". Not separable with certainty from the adult of Phyllocnistis labyrinthella.

Yellowish green with light brown head capsule.

A very long, winding corridor on the upperside of a leaf, never on the underside, and the mine never crosses itself. Sometimes, the mine occupies the entire leaf surface. The frass is concentrated in a continuous central, rather broad and dark green frass, distinguising it from the narrow, and almost black frassline in Phyllocnistis labyrinthella.
See also gracillariidae.net and bladmineerders.be.

No real cocoon, but a flimsy membrane; pupa yellowish brown.

The eggs are oviposited on the upperside of a leaf.
No real cocoon, but a flimsy membrane at the leaf margin; the leaf margin folds over the membrane. Pupation under the membrane.
The adults are active at dusk. The species hibernates in the adult stage.

The species lives mainly on Populus alba, bit it has also been recorded from Populus canescens.