Picture taken at Targasonne, Alta Cerdanya, Catalogne Nord, Orietnal Pyrenees, France, on granite, 1.650 m. altitude, exposed rocks.
Thallus matt, yellow-brown to dark reddish brown, very variable in colour, very thick. Apothecia without crystals and like burned areas. Apothecia 0,2-1 mm, sunken in the areoles.
Very frequent in the Pyrenees on siliceous rocks visited by birds.
be careful, not confusing it with Acarospora nitrophila. See my comment in this virtual guide. Both could appear together in the same boulder.