Phaeophyscia sciastra
| Phaeophyscia sciastra | |
|---|---|
| Scientific classification | |
| Domain: | Eukaryota |
| Kingdom: | Fungi |
| Division: | Ascomycota |
| Class: | Lecanoromycetes |
| Order: | Caliciales |
| Family: | Physciaceae |
| Genus: | Phaeophyscia |
| Species: | P. sciastra
|
| Binomial name | |
| Phaeophyscia sciastra (Ach.) Moberg (1977)
| |
| Synonyms[1] | |
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List
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Phaeophyscia sciastra, commonly known as the dark shadow lichen or the five o'clock shadow,[2] is a widespread species of foliose lichen in the family Physciaceae.[3] This rock-dwelling species tend to form rosettes on sun-exposed rocks, especially sandstone. The thalli, which grow up to 5 cm (2.0 in) in diameter and are closely attached to their substrate, are made of flat to convex lobes typically up to 0.5 mm wide.[4] The lichen occurs in Africa, Asia, Europe, and North America, and is one of the most widespread members of its genus in boreal and subtropical regions.
The prominent characteristic of Phaeophyscia sciastra is the presence of black, granular isidia that occur in both laminal and marginal areas of the thallus.[5] Apothecia (fruiting bodies) occur rarely in this species. All chemical spot tests are negative on P. sciastra, implying the absence of any secondary metabolites (lichen products). Individuals or populations of P. sciastra with longer lobes and that lack isidia tend to resemble P. decolor.[2]
It was first formally described as a new species in 1803 by the Swedish lichenologist Erik Acharius, who classified it in the genus Parmelia.[6] After having been transferred to other genera and sometimes treated as a subtaxon of other species in its taxonomic history,[1] another Swedish lichenologist, Roland Moberg, reclassified it to Phaeophyscia in 1977.[7]
References
- ^ a b "GSD Species Synonymy. Current Name: Phaeophyscia sciastra (Ach.) Moberg, Symb. bot. upsal. 22(no. 1): 47 (1977)". Species Fungorum. Retrieved 15 February 2025.
- ^ a b Brodo, Irwin M.; Sharnoff, Sylvia Duran; Sharnoff, Stephen (2001). Lichens of North America. New Haven: Yale University Press. p. 544. ISBN 978-0-300-08249-4.
- ^ "Phaeophyscia sciastra (Ach.) Moberg". Catalogue of Life. Species 2000: Leiden, the Netherlands. Retrieved 15 February 2025.
- ^ McMullin, R. Troy (2023). Lichens. The Macrolichens of Ontario and the Great Lakes Region of the United States. Firefly Books. p. 379. ISBN 978-0-228-10369-1.
- ^ Moberg, Roland (1993). "The lichen genus Phaeophyscia in South America with special reference to Andean species". Opera Botanica. 121: 281–284.
- ^ Acharius, E. (1803). Supplementum species quamplures novas descriptas nec non observationes varias complectens, quod praeviae suae Methodo Lichenum adjunxit Auctor (S. A. et L.) (in Latin). p. 49.
- ^ Moberg, R. (1977). The lichen genus Physcia and allied genera in Fennoscandia. Symbolae Botanicae Upsalienses. Vol. 22. pp. 1–108 [47].