Irish lichens

Buellia disciformis

Order: Lecanorales       Family: Physciaceae

Species: Buellia disciformis

Growth type crustose.
Photos: On Ash. Co. Cork, SW Ireland. Left identified by Andy Acton

Thallus thin and smooth to thick and cracked, whitish to pale yellow-grey, often with black prothallus. Apothecia with flat to slightly convex black discs, the margins usually persistent. Asci 8-spored, spores brown, 1-septate, 17-26 x 7-10 Ám. Micro photo below.
Thallus K+ clear yellow, C-, P+/- yellow, UV-

Can be frequent on twigs, branches and trunks of smooth-barked trees. Mainly found in west and north of Ireland.

Similar: Lecidella elaeochroma. Usually C+ orange, simple spores Diplotomma pharcidium can appear similar but is very rare. Spores 3-septate to sub-muriform

Buellia disciformis

Buellia disciformis

Microscope photograph
Buellia disciformis, asci and spores
Buellia disciformis March 2010 and January 2012

Please contact me if you find errors. All images used are copyright.