LICHALP

Psoroma tenue Henssen var. boreale Henssen

Lichenised.

Substrate: calciferous soil, acidic soil (mostly on siliceous substrata), , plant debris, living mosses

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 lichen weak in competition found on wet, naked soil, near glaciers or late snow-beds; certainly more widespread in the nival belt of the Alps, but easily confused with P. hypnorum.