Opegrapha rupestris Pers.

Syn.: Opegrapha monspeliensis Nyl., Opegrapha persoonii (Ach. ex Gray) Chevall., Opegrapha saxatilis DC., Opegrapha saxicola Ach. non auct.
Non- or doubtfully lichenised.
Substrate: calciferous rocks,
Altitudinal range: from the mesomediterranean belt (potential vegetation: evergreen broad-leaved forests dominated by Quercus ilex) 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: an ecologically wide-ranging, non-lichenised species found both in natural habitats (especially shaded niches of calcareous rocks in woodlands), and in moderately disturbed situations (such as on north-facing walls); it often grows on Verrucariaceae (especially Bagliettoa- and Verrucaria-species).
Austria: Vorarlberg; Tirol; Salzburg; Kärnten; Steiermark; Oberösterreich; Niederösterreich (incl. Wien); Germany: Oberbayern; France: Alpes-de-Haute-Provence; Alpes-Maritimes; Drôme; Savoie; Haute-Savoie; Vaucluse; Var; Italy: Friuli; Veneto; Trentino Alto Adige; Lombardia; Piemonte; Liguria; Slovenia: Alpine and Pre-Alpine Slovenia;