Bryonora pruinosa (Th. Fr.) Holt.-Hartw.

Syn.: Lecanora castanea (Hepp) Th. Fr. var. pruinosa Th. Fr.
Lichenised.
Substrate: living mosses, plant debris
Altitudinal range: from the subalpine belt (potential vegetation: open, taiga-like forests dominated by Larix decidua and/or Pinus cembra and Rhododendron) to the alpine belt (potential vegetation: treeless Alpine grasslands and tundras, to the lower limit of perennial snow and the equilibrium line of glaciers)
Note: similar to B. castanea, but apothecial margin darker than the occasionally pruinose disc, and ascospores less than 16 µm long; on plant debris and moribund lichens; in Europe it has an arctic-alpine distribution, but is apparently rare in the Alps.
Austria: Tirol; Switzerland: Graubünden; Luzern; Schwyz; Valais;