''Flavoplaca arcis'' is a species of saxicolous (rock-dwelling),

crustose Crustose is a habit of some types of algae and lichens in which the organism grows tightly appressed to a substrate, forming a biological layer. ''Crustose'' adheres very closely to the substrates at all points. ''Crustose'' is found on rocks and ...

squamulose A squamulose lichen is a lichen that is composed of small, often overlapping "scales" called squamules. If they are raised from the substrate and appear leafy, the lichen may appear to be a foliose lichen, but the underside does not have a "skin ...

(scaley)

lichen A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship.Teloschistaceae The Teloschistaceae are a large family of mostly lichen-forming fungi belonging to the class Lecanoromycetes in the division Ascomycota. The family, estimated to contain over 1800 species, was extensively revised in 2013, including the creation o ...

. Although widely distributed in Northern, Central, and Western Europe, it is not commonly encountered.

Taxonomy

The species was first scientifically described by lichenologists Josef Poelt and

Antonín Vězda Antonín (Toni) Vězda (25 November 1920 – 10 November 2008) was a Czech lichenologist. After completing a university education that was postponed by World War II, Vězda taught botany at the Czech University of Life Sciences Prague, Czech U ...

in 2006, as a member of genus ''

Caloplaca ''Caloplaca'' is a lichen genus comprising a number of distinct species. Members of the genus are commonly called firedot lichen, jewel lichen.Field Guide to California Lichens, Stephen Sharnoff, Yale University Press, 2014, gold lichens, "ora ...

''. Ulf Arup and colleagues transferred the

taxon In biology, a taxon (back-formation from ''taxonomy''; plural taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular nam ...

to the genus ''

Flavoplaca ''Flavoplaca'' is a genus of crust-like or scaly lichens in the family Teloschistaceae. It has 28 species with a mostly Northern Hemisphere distribution. Taxonomy The genus was circumscribed in 2013 by Ulf Arup, Patrik Frödén and Ulrik Søch ...

'' in 2013, following a

molecular phylogenetics Molecular phylogenetics () is the branch of phylogeny that analyzes genetic, hereditary molecular differences, predominantly in DNA sequences, to gain information on an organism's evolutionary relationships. From these analyses, it is possible to ...

-based restructuring of the family

Teloschistaceae The Teloschistaceae are a large family of mostly lichen-forming fungi belonging to the class Lecanoromycetes in the division Ascomycota. The family, estimated to contain over 1800 species, was extensively revised in 2013, including the creation o ...

Description

''Flavoplaca arcis'' features a

to slightly (scale-like)

thallus Thallus (plural: thalli), from Latinized Greek (), meaning "a green shoot" or "twig", is the vegetative tissue of some organisms in diverse groups such as algae, fungi, some liverworts, lichens, and the Myxogastria. Many of these organisms wer ...

with a bright yellow colour. The thallus is made up of wavy (small, discrete areas), sometimes arranged in a rosette-shaped, that can be wavy with minute around their periphery. These areoles are rather thick, ranging in diameter from 0.4 to 2 mm, and some are adorned with coarse, spherical reproductive structures known as , which match the colour of the thallus. These blastidia are distributed across the surface and edges of the areoles, with a particularly heavy concentration at the centres of the thalli. Reproductive structures known as are in form (with a that is surrounded by a pale , which has both algal and fungal cells), (attached flatly) to , yellow, and between 0.3 and 1.5 mm in width. When tested with a solution of

potassium hydroxide Potassium hydroxide is an inorganic compound with the formula K OH, and is commonly called caustic potash. Along with sodium hydroxide (NaOH), KOH is a prototypical strong base. It has many industrial and niche applications, most of which exp ...

(the K spot test), the thallus shows a purple reaction, which is a diagnostic feature for identification.

Habitat and distribution

''Flavoplaca arcis'' is found across a wide range of localities in Europe, although it is not commonly reported. Its distribution spans Western and Central Europe,

Scandinavia Scandinavia; Sámi languages: /. ( ) is a subregion#Europe, subregion in Northern Europe, with strong historical, cultural, and linguistic ties between its constituent peoples. In English usage, ''Scandinavia'' most commonly refers to Denmark, ...

, the Mediterranean region, the

Balkan Peninsula The Balkans ( ), also known as the Balkan Peninsula, is a geographical area in southeastern Europe with various geographical and historical definitions. The region takes its name from the Balkan Mountains that stretch throughout the who ...

, and the

Canary Islands The Canary Islands (; es, Canarias, ), also known informally as the Canaries, are a Spanish autonomous community and archipelago in the Atlantic Ocean, in Macaronesia. At their closest point to the African mainland, they are west of Morocc ...

. This species has an affinity for both

silicate In chemistry, a silicate is any member of a family of polyatomic anions consisting of silicon and oxygen, usually with the general formula , where . The family includes orthosilicate (), metasilicate (), and pyrosilicate (, ). The name is al ...

and

calcareous 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 adje ...

rocks and stones. Beyond natural habitats, ''Flavoplaca arcis'' is also known to colonise man-made structures. It is typically found in locations that are relatively exposed to the elements and can be found on both vertical and horizontal surfaces.

References

{{Taxonbar, from=Q25637579 arcis Lichen species Lichens described in 2006 Lichens of Europe Lichens of Macaronesia Taxa named by Josef Poelt Taxa named by Antonín Vězda