(Hübner, )Wingspan 19-22 mm.
A reasonably common species distributed from southern England northwards into southern Scotland and west into Ireland. It is similar to other British Acrobasis species but can appear more greyish.
The adults are on the wing during July and August, when they can be attracted to light.
Oak (Quercus) is the foodplant, the larvae feeding gregariously in spun leaves.