Acarospora fuscata

{{Short description|Species of fungus}}

{{Speciesbox

| image = Acarospora_fuscata_(EU).jpg

| image_caption =

| width =

| status = G5

| status_system = TNC

| status_ref = {{cite NatureServe |id=2.122304 |title=Acarospora fuscata |access-date=9 July 2025}}

| taxon = Acarospora fuscata

| authority = (Nyl.) Th.Fr. (1871)

| synonyms_ref =

| synonyms = *Lichen fuscatus Schrad. (1794)

• Lecanora badia var. fuscata Ach. (1810)
• Lecanora fuscata Röhl. (1813)
• Lecanora fuscata Nyl. (1863)
• Acarospora veronensis var. fuscata (Nyl.) Arnold (1870)

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Acarospora fuscata ("brown cobblestone lichen") is a glossy pale or yellowish-brown areolate lichen with angular areolas that grows up to {{convert|10|cm|in|0|abbr=on}} wide on non-calcareous rock in low and high elevations.Field Guide to California Lichens, Stephen Sharnoff, Yale University Press, 2014, {{ISBN|978-0-300-19500-2}}{{rp|217}}Lichen Flora of the Greater Sonoran Desert Region. Vol 3., Nash, T.H., Ryan, B.D., Gries, C., Bugartz, F., (eds.) 2001, [http://lichenportal.org/portal/taxa/index.php?taxon=52997] It grows in Europe and North America. It grows in southern California and on the eastern part of the Sierra Nevada range.{{rp|217}} It may grow with the areolas disconnected.{{rp|217}} The areolas may lift at the edges, but the areolas do not overlap like true squamules (sub-squamulose).{{rp|217}} More common in the Sierras is the similar species Acarospora thamnina, which is truly squamulose with overlapping scales.{{rp|217}}

Image:Acarospora_fuscata_(EU1).jpg

It usually has 0-1 apothecium per areole, which may be point-like (punctiform) or fill the entire areole with a disc that is rough surfaced and reddish brown. The asci are club shaped (clavate), with over 100 spores. Lichen spot tests are K−, C+ vaguely pink, KC+ red, and P−.{{rp|217}} Secondary metabolites include gyrophoric acid.