Wingspan c.8 mm
A fairly local species with a distribution covering parts of England and Wales, and the Scottish Highlands.
The larvae feed from August to October on birch Betula, forming a large blister-mine on the underside of a leaf, occupying most of the leaf and causing it to pucker quite strongly. The mine has a number of strong creases on the lower epidermis.
Adult moths are on the wing in June and July.