LICHALP

Rhizocarpon subpostumum (Nyl.) Arnold

Syn.: Lecidea subpostuma Nyl.

Lichenised. Poorly known taxon.

Substrate: siliceous rocks, intermediate rocks (such as calciferous schists), bark

Altitudinal range: from the montane belt (potential vegetation: deciduous forests dominated by Fagus sylvatica and closed coniferous forests with Picea abies) 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 silicicolous species resembling Rh. postumum in the small apothecia and the small submuriform ascospores, but thallus paler and usually containing gyrophoric acid, exciple in section with Atra-red, reacting K+ purple; widespread in Europe, from the boreal to temperate-alpine zones, mainly under oceanic conditions; from the Alps there are only a few scattered records, but probably the species was not always distinguished.