Acarospora smaragdula

Purvis, O. W., Williamson, B., Bartok, K. Zoltani, N. (2000). Bioaccumulation of lead by the lichen Acarospora smaragdula from smelter emissions. New Phytologist, 147, 591-9. 

Certain lichens (Acarospora smaragdula, Lecidea lactea, Lecidella bullata, Tephromela testaceoatra) from cupriferous substrata form complexes of copper with norstictic acid (367) (593) and psoromic acid (368) (594). 

They considered the third explanation (c) to be the most plausible because large amounts of Fe can be observed frequently on the cell walls, in intercellular spaces, and even as a coating over the outer surfaces of thethalliof Acarospora sinopica, A. smaragdula f subochracea, and Rhizocarpon oederi. 

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