Picture taken at Estevar, Cerdanya, Oriental Pyrenees, on calcareous rock, cemetery.
chalky
Placodioid thallus, rosette foring, matt white, lobes widening towards the tips, irregular surface, without soralia or isidia, apothecia frequent, from 1 to 1,5 mm in diameter. Disc black sometimes with white pruina, thallin margin disappearing.