''Acarospora fuscata'' ("brown cobblestone lichen") is a glossy pale or yellowish-brown

areolate Lichens are symbiotic organisms made up of multiple species: a fungus, one or more photobionts (an alga and/or a cyanobacteria) and sometimes a yeast. They are regularly grouped by their external appearance – a characteristic known as their gro ...

lichen A lichen ( , ) is a hybrid colony (biology), colony of algae or cyanobacteria living symbiotically among hypha, filaments of multiple fungus species, along with yeasts and bacteria embedded in the cortex or "skin", in a mutualism (biology), m ...

with angular areolas that grows up to wide on non-

calcareous rock Calcareous () is an adjective meaning "mostly or partly composed of calcium carbonate", in other words, containing lime or being chalky. The term is used in a wide variety of scientific disciplines. In zoology ''Calcareous'' is used as an adjec ...

in low and high elevations.Field Guide to California Lichens, Stephen Sharnoff, Yale University Press, 2014, Lichen Flora of the Greater Sonoran Desert Region. Vol 3., Nash, T.H., Ryan, B.D., Gries, C., Bugartz, F., (eds.) 2001

/ref> It grows in Europe and North America. It grows in southern

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

and on the eastern part of the

Sierra Nevada The Sierra Nevada ( ) is a mountain range in the Western United States, between the Central Valley of California and the Great Basin. The vast majority of the range lies in the state of California, although the Carson Range spur lies primari ...

range. It may grow with the areolas disconnected. The areolas may lift at the edges, but the areolas do not overlap like true squamules ( sub-squamulose). More common in the Sierras is the similar species '' Acarospora thamnina'', which is truly squamulose with overlapping scales. It usually has 0-1

apothecium An ascocarp, or ascoma (: ascomata), is the fruiting body ( sporocarp) of an ascomycete phylum fungus. It consists of very tightly interwoven hyphae and millions of embedded asci, each of which typically contains four to eight ascospores. Ascoc ...

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 This glossary of entomology describes terms used in the formal study of insect species by entomology, entomologists. A–C A synthetic chlorinated hydrocarbon insecticide, toxic to vertebr ...

), with over 100

spores In biology, a spore is a unit of sexual (in fungi) or asexual reproduction that may be adapted for dispersal and for survival, often for extended periods of time, in unfavourable conditions. Spores form part of the life cycles of many plant ...

. Lichen spot tests are K−, C+ vaguely pink, KC+ red, and P−.

Secondary metabolite Secondary metabolites, also called ''specialised metabolites'', ''secondary products'', or ''natural products'', are organic compounds produced by any lifeform, e.g. bacteria, archaea, fungi, animals, or plants, which are not directly involved ...

s include

gyrophoric acid Gyrophoric acid is a tridepside. It is a double ester of the orsellinic acid. It can also be found in most of the species of the lichen genera '' Actinogyra'', '' Lasallia'', and '' Umbilicaria'' . Natural occurrence and biosynthesis Gyropho ...

References

fuscata Lichen species Lichens described in 1863 Lichens of Europe Lichens of North America Taxa named by William Nylander (botanist) {{Lecanoromycetes-stub