A species with a whitish to light grey, often pruinose thallus, 4-spored asci and the content of lecanoric acid (C+ red). It grows in calcareous rocks, usually on their vertical surfaces at any elevation. The lichen has a cosmopolitan distribution. In Europe, it is common, especially in the Mediterranean (Lumbsch 1989). In the Czech Republic, it occurs sparsely to rarely on limestones in karst areas. It may be aslo found on calcareous vulcanites, sandstones, and exceptionally even in anthropogenic habitats (e.g. on castle walls).taxonomic classification:
All records: 32, confirmed 26. One click on a selected square displays particular record(s), including their source(s).