Order: Lecanorales       Family: Ramalinaceae Cliostomum griffithii Growth type crustose. Identified by John Douglass Photos: On bark. Droum Wood, Co. Cork, SW Ireland. Very variable. Whitish-grey thallus with numerous small, black pycnidia. Often infertile but when present the apothecia are pinkish, light brown or brown-black, often pruinose and becoming convex and distorted. Thin, lighter coloured margins that darken with age. The spores are 1-septate, 8-15 x 2-4 µm. Micrographs below. Thallus K+ yellow, pycnidia walls K+ purple. Found on the drier side of acid-barked trees and wooden posts, rarely on shaded rocks. Moderately pollution tolerant. Similar: Cliostomum tenerum is found on acidic coastal rocks

Microscope photographs



Cliostomum griffithii January 2012