Sporodictyon schaererianum A. Massal.

Syn.: Polyblastia schaereriana (A. Massal.) Müll. Arg., Polyblastia subpyrenophora (Leight.) Zschacke, Verrucaria subpyrenophora Leight.
Lichenised.
Substrate: calciferous rocks, intermediate rocks (such as calciferous schists), siliceous rocks
Altitudinal range: from the montane belt (potential vegetation: deciduous forests dominated by Fagus sylvatica and closed coniferous forests with Picea abies) to the nival belt (above the lower limit of perennial snow and glaciers)
Note: a mainly circum-arctic to boreal-montane lichen found on hard calciferous rocks, often on dolomite, but also on calcareous sandstone and schist in cold-humid situations, with optimum above treeline.
Austria: Vorarlberg; Salzburg; Kärnten; Germany: Oberbayern; Schwaben; Switzerland: Bern; Luzern; Schwyz; Vaud; France: Alpes-Maritimes; Haute-Savoie; Italy: Trentino Alto Adige; Lombardia; Piemonte; Valle d'Aosta;