Taxon
General Description
On a granite tor, Dartmoor and on a wall in lead mine workings, mid Wales (Ceredigion). Similar to M. smaragdula, but with a thicker thallus, with larger and strongly convex areoles or squamules.
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References
Knudsen, K., Kocourková, J., Cannon, P., Coppins, B., Fletcher, A. & Simkin, J. (2021). Acarosporales: Acarosporaceae, including the genera Acarospora, Caeruleum, Myriospora, Pleopsidium, Sarcogyne and Trimmatothelopsis. Revisions of British and Irish Lichens 12: 1-25. Link