About Circinaria calcarea (L.) A.Nordin, Savić & Tibell
Circinaria calcarea (L.) A.Nordin, Savić & Tibell is a species of crustose lichen belonging to the family Megasporaceae. Carl Linnaeus first formally published this as a new species in his 1753 work Species Plantarum. At the time, Linnaeus classified all lichens in the genus Lichen, so he named it Lichen calcareus. This species has had a long and complex taxonomic history, which has led to the creation of dozens of synonyms. In 2010, following molecular phylogenetic analysis of the Megasporaceae family, the species was transferred to its current genus Circinaria. Circinaria calcarea has a cosmopolitan distribution, and has been recorded growing in the Arctic, Asia, Australasia, Europe, Oceania, Central America, South America, and North America. It is a saxicolous (rock-dwelling) lichen that grows on calcareous, calciferous, and basic rock.
