Wingspan c.8 mm.
This diminutive species varies in the intensity of the grey ground colour; some individuals are quite dark with distinct whiter fasciae, some have rather less contrasting markings.
The larvae mine the blades of various grasses, including meadow-grass (Poa spp.) and cock's-foot (Dactylis glomerata).
There are two generations, with moths on the wing from late April to June and again from late July to September. The larval mines can be found from March to April and in July.
The species is widespread and reasonably common throughout much of the British Isles except the very far north.