Altitudinal range: from the alpine belt (potential vegetation: treeless Alpine grasslands and tundras, to the lower limit of perennial snow and the equilibrium line of glaciers) to the nival belt (above the lower limit of perennial snow and glaciers)
Note: a species resembling Rh. postumum, but thallus inconspicuous, exciple reacting K+ purple-brown, and ascospores somewhat smaller (to c. 20 µm long); not consistently distinguished from Rh. postumum and specific difference in need of re-evaluation; on schistose outcrops in shaded situations above treeline; only reported from the Eastern Alps (Austria).
