The genus Miriquidica, which comprises c. 30 saxicolous species worldwide, was mainly circumscribed by the presence of miriquidic acid (in most species) and by anatomical characters of the apothecia, e.g., asci of the Lecanora-type. It belongs to the Lecanoraceae and consists of species previously placed partly in Lecidea and partly in Lecanora. The genus has been treated e.g. by Rambold & Schwab (1990), Andreev (2004), Singh & al. (2013) and Hafellner & al. (2014). Preliminary results from a comprehensive study by Haugan & al. (2016) show the presence of several cryptic species, and demonstrate that the genus, as currently circumscribed, is polyphyletic. Even after the transfer of some species to other genera, Miriquidica remains paraphyletic, with species of Protoparmelia, Lecanora, Lecidea s.lat., and Myochroidea nested, so that several nomenclatural changes are to be expected. Most species occur on siliceous rocks in the boreal to arctic-alpine zones.
This key includes all species known to occur in Italy (see Nimis 2016), plus a few species known from the Alps outside the Italian territory Nimis & al. (2018), which should be looked for in Italy, for a total of 17 infrageneric taxa.

References

Andreev M.P. 2004. Notes on the lichen genus Miriquidica (Lecanorales, Lecanoraceae) in Russia. Bibl. Lichenol., 88: 15-42.
Hafellner J., Obermayer W., Tretiach M. 2014. Miriquidica invadens, an obligate youth parasite on Sporastatia, with remarks and a key to species of the M. griseoatra-group. Lichenologist, 46, 3: 1-30.
Haugan R., Timdal E., Frisch A., Rui S., Bendiksby M. 2016. Miriquidica - yet another non-monophyletic lichen genus rich in cryptic species. IAL 8, Book of Abstracts, Helsinki: 163.
Nimis P.L. 2016. The lichens of Italy. A second annotated catalogue. EUT, Trieste, 740 pp.
Nimis P.L., Hafellner J., Roux C., Clerc P., Mayrhofer H., Martellos S., Bilovitz P.O. 2018. The Lichens of the Alps. An Annotated Catalogue. Mycokeys, 31: 1-634.
Rambold G., Schwab A.J. 1990. Rusty coloured species of the lichen genus Miriquidica (Lecanoraceae). Nordic J. Bot., 10, 1: 117-121.
Singh G., Dal Grande F., Divakar P.K., Otte J., Leavitt S.D., Szczepanska K., Crespo A., Rico V.J., Aptroot A., Cáceres M.E., Lumbsch H.T., Schmitt I. 2015. Coalescent-based species delimitation approach uncovers high cryptic diversity in the cosmopolitan lichen-forming fungal genus Protoparmelia (Lecanorales, Ascomycota). PlosOne, DOI:10.1371/journal.pone.0124625 May 1, 2015.

Last modified: September, 12, 2022

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