Fungi Outer Hebrides

Family: Lecideaceae

Porpidia cinereoatra (Ach.) Hertel & Knoph

Type: Crustose

White to greyish, thick and crazed thallus, with a black prothallus. Common on siliceous rocks but a difficult genus to identify. (Good tip from Neil Sanderson: K/UV + bright mauve fluorescence)

Paul Cannon

Smith et al. editors (2009) The Lichens of Great Britain and Ireland
Dobson (2018) Lichens: an Illustrated Guide to the British and Irish Species