A crust forming lichen with a thin white to greyish thallus and white prothallus. Apothecia with brownish-grey discs covered by thick white pruina.

Found on the twigs, branches and young trunks of smooth barked deciduous trees, very rarely occurs on stonework.

All year round.

Widespread and fairly frequent in much of Britain.

Status in Leicestershire and Rutland not known.