Thallus of ascending thin squamules to 4 mm broad, upper side brown or greenish brown with white margins, sometimes faintly pruinose; margins entire or deeply lobate; underside pale brown to white, medulla thin; lower cortex of longitudinal and cross-oriented hyphae hymenium 60-80 μm, hyaline; paraphyses 2-2.5 μm, tips 5-6 μm and heavily pigmented; asci clavate; spores with swellings to each side of porus, Buellia-type, septum prominent, 10-15 x 6-8.3 μm.

This species grows on siliceous rocks, sometimes on other lichens. It is known from northern Europe and rarely in the American Arctic.