Irish lichens

Caloplaca variabilis

Order: Teloschistales       Family: Teloschistaceae

Species: Caloplaca variabilis (Pyrenodesmia variabilis)

Growth type crustose
Photos: On concrete. Aughinish, Co. Limerick, W Ireland.
Identification needs confirming

Grey to greyish-brown, areolate, rounded thallus, sometimes with a dark prothallus. Sessile apothecia with grey-blue pruinose black discs. The epithicium is pale, K+ purple. Thallus K-.
Spores 14-16 x 7-9 Ám, the septum 2-3 Ám wide.

Found on nutrient-rich calcareous rocks, walls and the horizontal copings of walls and bridges.

Caloplaca variabilis. December 2009

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