Caloplaca rubroaurantiaca B. de Lesd.

Lichenised. Poorly known taxon.
Substrate: siliceous rocks
Altitudinal range: from the mesomediterranean belt (potential vegetation: evergreen broad-leaved forests dominated by Quercus ilex) to the subalpine belt (potential vegetation: open, taiga-like forests dominated by Larix decidua and/or Pinus cembra and Rhododendron)
Note: a member of the difficult C. arenaria-group, characterised by smaller spores with a thinner septum and the orange apothecia, with some scattered records from the Alps.
Switzerland: Valais; France: Alpes-de-Haute-Provence; Haute-Alpes; Alpes-Maritimes; Italy: Piemonte; Valle d'Aosta; Liguria;