Head white; forewing ground colour silvery white, sometimes darkened with very light ochreous scales; the dorsal half of the apical area often darkened with greyish brown scales; 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 three dark brown hooks depart into the cilia.
The summer generation has the basal part of the forewing white, whereas the late, hibernating generation has dark grey suffusion in the basal part of the forewing. This suffusion may form an ill-defined longitudinal fascia.

A long winding corridor on the upper side of a leaf. The frass is concentrated in a very narrow central frass line; the mine itself has a yellowish appearance, distinguishing it from the other Phyllocnistis mines.
See also gracillariidae.net and bladmineerders.be.

No real cocoon, but a flimsy spinning which is not pure white as in most other Phyllocnistis species, but greenish or yellowish.

The eggs are oviposited mainly on the upperside of the leaf.
Pupation under a flimsy membrane at the end of the corridor at the margin of a leaf, which is turned over the membrane.
The adults are active at dusk and hibernate in the adult stage.

The caterpillar lives on different species of narrow-leaved Salix trees, like Salix alba, S. babylonica, S. fragilis, and S. triandra.