Arthrorhaphis vacillans Th. Fr. & Almq. ex Th. Fr.

Syn.: Arthrorhaphis anziana (Lynge) Poelt, Bacidia anziana Lynge, Bacidia vacillans (Th. Fr. & Almq. ex Th. Fr.) Rostr.
Lichenised.
Substrate: acidic soil (mostly on siliceous substrata), , calciferous soil,
Altitudinal range: from the subalpine belt (potential vegetation: open, taiga-like forests dominated by Larix decidua and/or Pinus cembra and Rhododendron) to the nival belt (above the lower limit of perennial snow and glaciers)
Note: an arctic-alpine, circumpolar species found in humid soil near and above treeline. It starts the life-cycle as a parasite of Baeomyces placophyllus, later becoming autotrophic, and is the most calcium-tolerant among the Arthrorhaphis-species, often occurring over calcareous schists and even marmor (Obermayer in litt.).
Austria: Tirol; Salzburg; Kärnten; Steiermark; Germany: Oberbayern; Switzerland: St. Gallen; ?Schwyz; Italy: Trentino Alto Adige;