Wingspan c10 mm.
Well distributed across mainland Britain, but fairly localised, this species is probably overlooked. The adults are golden, marked with purplish, with a distinct pale tornal triangular spot, and a smaller costal spot. The head is covered with yellowish hairs.
The larvae mine the leaves of birch Betula during May and June. The species is the latest of the birch-feeders with the exception of Eriocrania sparrmannella, which feeds mainly in July and August.
The leafmine begins as a narrow gallery in the centre of the leaf, turning into an elongate blotch and then a larger blotch encompassing the leaf margin.
Leafmine (British Leaf Mining Fauna)