Wingspan 7 to12 mm. This small moth has dark brownish-black wings speckled with cream. The cream marks seem to produce two pale diamonds along the back where the wings meet. The female moth is slightly smaller than the male.

Both can be found resting on tree trunks during the flight period.

Flying in June and July.

The larva lives in a case, and attaches itself to a tree-trunk, fence or other lichen-covered surface.

A fairly common species throughout England and Wales, extending into southern Scotland. In the Butterfly Conservation's Microlepidoptera Report 2011 this species was classified as common.

It appears to be uncommon in Leicestershire and Rutland, where there are few records. L&R Moth Group status = D (rare or rarely recorded).