Common in damp woodland throughout much of the British Isles. In Hampshire and on the Isle of Wight apparently well-distributed, but like many leaf miners, probably under-recorded in north Hampshire away from the M3 corridor, and in the New Forest. Wingspan 7-9 mm. Imago does not readily come to light, and more frequently recorded in the larval stage, when mines are relatively easy to find where they are present. Larva mines leaves of Alder and Italian Alder, over-wintering as a pupa in a cocoon.