Ramalinaceae Lecania turicensis Growth type crustose. Chemical results negative The most frequent saxicolous Lecania species. Very common on both calcareous and non-calcareous rocks and on mortar. White or greyish, deeply-cracked areolate thallus with very crowded apothecia, the discs reddish-brown to black. Thallus and apothecia usually +/- pruinose. Spores are 1-septate, 10.5-13 × 4.5-6 µm. Micrograph below. A member of the Lecania erysibe s. lat group Similar: Lecania atrynoides, non-pruinose discs speckled brown when wet. Lecania rabenhorstii, only apothecia and margins are pruinose

Microscope photograph

Lecania turicensis
Lytchett Minster, Dorset. December 2016