''Pyrenodesmia micromontana'' is a species of saxicolous (rock-dwelling),

crustose lichen Crustose lichens are lichens that form a crust which strongly adheres to the Substrate (biology), substrate (soil, rock, tree bark, etc.), making separation from the substrate impossible without destruction. The basic structure of crustose lichen ...

in 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 ...

. Found in the

Orenburg Orenburg (russian: Оренбу́рг, ), formerly known as Chkalov (1938–1957), is the administrative center of Orenburg Oblast, Russia. It lies on the Ural River, southeast of Moscow. Orenburg is also very close to the Kazakhstan-Russia bor ...

region of Russia, this species prefers to grow on

lime Lime commonly refers to: * Lime (fruit), a green citrus fruit * Lime (material), inorganic materials containing calcium, usually calcium oxide or calcium hydroxide * Lime (color), a color between yellow and green Lime may also refer to: Botany ...

-rich

schist Schist ( ) is a medium-grained metamorphic rock showing pronounced schistosity. This means that the rock is composed of mineral grains easily seen with a low-power hand lens, oriented in such a way that the rock is easily split into thin flakes o ...

and

sandstone Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar (both silicates) ...

boulders and pebbles in

scrubs Scrub(s) may refer to: * Scrub, low shrub and grass characteristic of scrubland * Scrubs (clothing), worn by medical staff * ''Scrubs'' (TV series), an American television program * Scrubs (occupation), also called "scrub tech," "scrub nurse," o ...

and

steppe In physical geography, a steppe () is an ecoregion characterized by grassland plains without trees apart from those near rivers and lakes. Steppe biomes may include: * the montane grasslands and shrublands biome * the temperate grasslands, ...

Taxonomy

The lichen was first formally described as a new species in 2016 by the lichenologists Ivan Frolov, Karina Wilk, and Jan Vondrák, who initially classified it in the 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 ...

''. The

type specimen In biology, a type is a particular wiktionary:en:specimen, specimen (or in some cases a group of specimens) of an organism to which the scientific name of that organism is formally attached. In other words, a type is an example that serves to a ...

was collected in Russia, specifically in the

region, within the Sakmara district near the village of Grebeni. This location features a shrubby

on the southeast slope of the Grebeni hill, west of the village. The specimen was found at an elevation ranging from above sea level, where it was found growing on

-rich

and

boulders and pebbles within a scree.

Josef Hafellner Josef Hafellner (1951– ) is an Austrian mycologist and lichenologist. He was awarded the Acharius Medal in 2016 for his lifetime contributions to lichenology. Before his retirement, he was a professor at the Karl-Franzens-Universität in Graz ...

and Roman Türk 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 genus ''

Pyrenodesmia ''Pyrenodesmia'' is a genus of lichen-forming fungi in the family Teloschistaceae. It has 23 species. The genus was circumscription (taxonomy), circumscribed in 1852 by Italian lichenologist Abramo Bartolommeo Massalongo. Species *''Pyrenodesmi ...

'' later that year.

Description

The

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 ...

of ''Pyrenodesmia micromontana'' is (growing on the rock surface), typically less than 150

μm The micrometre ( international spelling as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American spelling), also commonly known as a micron, is a unit of length in the International System of Unit ...

thick, and shows no distinct . It is

ochre Ochre ( ; , ), or ocher in American English, is a natural clay earth pigment, a mixture of ferric oxide and varying amounts of clay and sand. It ranges in colour from yellow to deep orange or brown. It is also the name of the colours produced ...

or grey in colour, forming small, roundish spots up to 1 cm in diameter or irregular spots spread over several centimetres. The thallus consists of tightly arranged, angular to rounded, flat . The medulla is inconspicuous, with cells containing extracellular crystals that dissolve and recrystallize in

sulfuric acid Sulfuric acid (American spelling and the preferred IUPAC name) or sulphuric acid ( Commonwealth spelling), known in antiquity as oil of vitriol, is a mineral acid composed of the elements sulfur, oxygen and hydrogen, with the molecular formu ...

. The , composed of spherical cells measuring 11.3–15.0 μm in diameter, is usually about 56–68 μm wide. Apothecia in ''Pyrenodesmia micromontana'' are small, usually less than 0.4 mm in diameter, with a brown to black and , and a matching the thallus colour. The

hymenium The hymenium is the tissue layer on the hymenophore of a fungal fruiting body where the cells develop into basidia or asci, which produce spores. In some species all of the cells of the hymenium develop into basidia or asci, while in others some ...

is colourless, occasionally containing crystals. The is grey, sometimes with a weak brown tinge. Chemical spot tests show that the thallus and apothecia are K−, C−, and P−. The uppermost cells in the cortex of the thallus contain the pigment .

Distribution and ecology

''Pyrenodesmia micromontana'' is found in various European and Asian inland territories, usually in mountainous regions. It grows on

limestone Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms whe ...

, lime-rich schist, and sandstone, often accompanied by lichen species such as '' Acarospora moenium'', '' Polyozosia dispersa'', and '' Sarcogyne regularis''. It does not occur in coastal areas where ''

Pyrenodesmia micromarina ''Pyrenodesmia micromarina'' is a species of saxicolous (rock-dwelling), crustose lichen in the family Teloschistaceae. It is found in the Eastern Mediterranean, specifically along the coasts of the Black Sea and the Sea of Marmara in Russia, T ...

'' is found.

References

{{Taxonbar, from=Q28055768 , from2=Q59564751 Teloschistales Lichen species Lichens described in 2016 Lichens of Asia Lichens of Europe