Thelidium grummannii Servít

Lichenised. Poorly known taxon.
Substrate: calciferous rocks
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: a calcicolous species with a mainly endolithic, greyish thallus with brown dots, semi-immersed perithecia (to c. 0.3 mm in diam.) with a thin thalline annulus, without involucrellum (?), and 1-septate, oblong ascospores (to c. 30 µm long); only known from the type locality in the Western Alps (Switzerland).
Switzerland: Bern;