Order: Teloschistales       Family: Teloschistaceae Species: Pyrenodesmia variabilis (Caloplaca variabilis) Growth type crustose Photos: On concrete. Aughinish, Co. Limerick, W Ireland. Grey to greyish-brown, areolate, rounded thallus, sometimes with a dark prothallus. Sessile apothecia with grey-blue pruinose black discs, the spores 14-16 x 7-9 µm, and the septum 2-3 µm wide. The epithecium is pale, K+ purple. Thallus K-. Found on nutrient-rich calcareous rocks, walls and the horizontal copings of walls and bridges.

Pyrenodesmia variabilis (Caloplaca variabilis). December 2009