''Pseudephebe pubescens'', also known as 'fine rock wool', is a

temperate In geography, the temperate climates of Earth occur in the middle latitudes (approximately 23.5° to 66.5° N/S of the Equator), which span between the tropics and the polar regions of Earth. These zones generally have wider temperature ran ...

alpine

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 ...

. It is a member of the genus '' Pseudephebe'', a lichen group characterized by dense mats of brown to near-black "hairs".

Taxonomy

Linnaeus Carl Linnaeus (23 May 1707 – 10 January 1778), also known after ennoblement in 1761 as Carl von Linné,#Blunt, Blunt (2004), p. 171. was a Swedish biologist and physician who formalised binomial nomenclature, the modern system of naming o ...

first described ''Lichen pubescens'' in 1753. Maurice Choisy transferred it to the genus '' Pseudephebe'' in 1930. It is usually distinguished from '' P. minuscula'' due to ''P. pubescens'' preferring a moister habitat, and its branches are more terete and lack the irregularities of ''P. minuscula.'' The morphological and ecological differences between the two species are often overlapping, and it can be difficult to truly distinguish the two without molecular analysis.

Description

''Pseudephebe pubescens'' is a

fruticose lichen A fruticose lichen is a form of lichen fungi that is characterized by a coral-like shrubby or bushy growth structure. It is formed from a symbiotic relationship of a photobiont such as green algae or less commonly cyanobacteria and one, two or m ...

that forms decumbent mats made of isotomic-dichotomous branching thalli. The branching occurs frequently and weaves around itself, leading to the woolen appearance. Dark brown to black in color and shiny.

Apothecia 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. As ...

are rare, but are rarely greater than 6 mm in diameter and have the same appearance as the rest of the thallus. The species lacks

isidia An isidium (plural: isidia) is a tiny, wart- or finger-like outgrowth on the thallus surface of certain lichen species. It is one of two principal types of vegetative reproduction, vegetative reproductive structures in lichens, the other being ...

soredia Soredia are common reproduction, reproductive structures of lichens. Lichens asexual reproduction, reproduce asexually by employing simple fragmentation and production of soredia and isidia. Soredia are powdery propagules composed of fungus, fung ...

, and pseudocyphellae.

Pycnidia A pycnidium (plural pycnidia) is an asexual fruiting body produced by mitosporic fungi, for instance in the order Sphaeropsidales ( Deuteromycota, Coelomycetes) or order Pleosporales (Ascomycota, Dothideomycetes). It is often spherical or inve ...

occur in great numbers on tubercles with conspicuous ostioles. It is not known to produce any secondary metabolites.

Habitat and distribution

''Pseudephebe pubescens'' is found specifically on acidic or silicate rocks in temperate-alpine or

sub-arctic The subarctic zone is a region in the Northern Hemisphere immediately south of the true Arctic, north of hemiboreal regions and covering much of Alaska, Canada, Iceland, the north of Fennoscandia, Northwestern Russia, Siberia, and the Cair ...

regions. It has circumpolar sightings, being found from the Canadian

territories A territory is an area of land, sea, or space, belonging or connected to a particular country, person, or animal. In international politics, a territory is usually a geographic area which has not been granted the powers of self-government, ...

, throughout the United States, and sometimes in alpine Mexico. It has been known in Europe, but recently discovered in China and even been found in the Andes and in Australia. It has been known to grow upon wood occasionally. ''Pseudephebe pubescens'' tends to be in more temperate environments than ''P. minuscula''.

References

{{Taxonbar, from=Q10679313 Parmeliaceae Lichen species Lichens described in 1753 Taxa named by Carl Linnaeus Lichens of North America