''Pyrenodesmia micromarina'' is a species of

saxicolous A saxicolous lichen is a lichen that grows on rock. The prefix "sax" from the Latin means "rock" or "stone". Characteristics Saxicolous lichens exhibit very slow growth rates. They may develop on rock substrates for long periods of time, give ...

(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 ...

. It is found in the

Eastern Mediterranean Eastern Mediterranean is a loose definition of the eastern approximate half, or third, of the Mediterranean Sea, often defined as the countries around the Levantine Sea. It typically embraces all of that sea's coastal zones, referring to communi ...

, specifically along the coasts of the

Black Sea The Black Sea is a marginal mediterranean sea of the Atlantic Ocean lying between Europe and Asia, east of the Balkans, south of the East European Plain, west of the Caucasus, and north of Anatolia. It is bounded by Bulgaria, Georgia, Roma ...

and the

Sea of Marmara The Sea of Marmara,; grc, Προποντίς, Προποντίδα, Propontís, Propontída also known as the Marmara Sea, is an inland sea located entirely within the borders of Turkey. It connects the Black Sea to the Aegean Sea via the ...

in Russia, Turkey, and Ukraine. It grows on coastal rocks and occasionally

concrete Concrete is a composite material composed of fine and coarse aggregate bonded together with a fluid cement (cement paste) that hardens (cures) over time. Concrete is the second-most-used substance in the world after water, and is the most wi ...

, often in Mediterranean scrub vegetation.

Taxonomy

The lichen was first formally described as a new species in 2016 by the lichenologists Ivan Frolov, Oleksandr Khodosovtsev, and Jan Vondrák, who placed 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 near Gaziköy in a small brook valley at elevations of above sea level. Frolov and Vondrák later transferred it to genus '' Pyrenodesmia''.

Description

This species of ''Pyrenodesmia'' is recognized by several key features: it lacks

anthraquinone Anthraquinone, also called anthracenedione or dioxoanthracene, is an aromatic organic compound with formula . Isomers include various quinone derivatives. The term anthraquinone however refers to the isomer, 9,10-anthraquinone (IUPAC: 9,10-dioxo ...

s (common in the family

), and its

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 ...

, which is usually thinner than 200

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 ...

, does not have a distinct cortex and has a colouration. The mature apothecia are typically smaller than 0.5 mm in diameter, with a black with a true, zeorine exciple. The thallus of ''Pyrenodesmia micromarina'' is ochre to grey, occasionally with white spots, and forms small, irregular to roundish spots. It consists of tightly arranged, flat . The

medulla Medulla or Medullary may refer to: Science * Medulla oblongata, a part of the brain stem * Renal medulla, a part of the kidney * Adrenal medulla, a part of the adrenal gland * Medulla of ovary, a stroma in the center of the ovary * Medulla of th ...

is inconspicuous, and the is made up of spherical cells. The is usually not developed, but an cortex might be present with an indistinct boundary. The lichen does not have vegetative diaspores and occasionally has a white , particularly around the

apothecia An ascocarp, or ascoma (), 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. Ascocarps are mo ...

. Apothecia are small, with a black and a that matches the thallus in 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 and may contain stacks of extracellular crystals. The

asci ASCI or Asci may refer to: * Advertising Standards Council of India * Asci, the plural of ascus, in fungal anatomy * Accelerated Strategic Computing Initiative * American Society for Clinical Investigation * Argus Sour Crude Index * Association of ...

are , containing eight , colourless with rather wide

septa The Southeastern Pennsylvania Transportation Authority (SEPTA) is a regional public transportation authority that operates bus, rapid transit, commuter rail, light rail, and electric trolleybus services for nearly 4 million people in five coun ...

. are commonly observed, with darker grey tops on the thallus surface. The are

ellipsoid An ellipsoid is a surface that may be obtained from a sphere by deforming it by means of directional scalings, or more generally, of an affine transformation. An ellipsoid is a quadric surface; that is, a surface that may be defined as the ...

to broadly ellipsoid.

Chemistry

Chemical tests reveal that the thallus and apothecia are negative for potassium hydroxide (K), calcium hypochlorite (C), and p-phenylenediamine (P) reactions and are not fluorescent under

ultraviolet Ultraviolet (UV) is a form of electromagnetic radiation with wavelength from 10 nanometer, nm (with a corresponding frequency around 30 Hertz, PHz) to 400 nm (750 Hertz, THz), shorter than that of visible light, but longer than ...

light. The and the outer cells of the contain , which reacts to water and potassium hydroxide. However, no substances were detected by

high-performance liquid chromatography High-performance liquid chromatography (HPLC), formerly referred to as high-pressure liquid chromatography, is a technique in analytical chemistry used to separate, identify, and quantify each component in a mixture. It relies on pumps to pa ...

in apothecia and thallus samples.

Distribution and ecology

''Caloplaca micromarina'' is a maritime species found in the Eastern Mediterranean, specifically along the coasts of the Black Sea and the Sea of Marmara in Russia, Turkey, and Ukraine. It grows on coastal rocks and occasionally

, often in Mediterranean scrub vegetation. The species co-occurs with various lichens including '' Aspicilia contorta'', '' Caloplaca conversa'', and ''

Candelariella aurella ''Candelariella aurella'', the hidden goldspeck lichen or eggyolk lichen, is a yellow crustose lichen in the family Candelariaceae. It is commonly found on calcareous rock or wood or bark exposed to sunlight and which may have calcareous dust in ...

''.

References

{{Taxonbar, from= , from2=Q28059780 Teloschistales Lichen species Lichens described in 2016 Lichens of Europe Lichens of Eastern Europe Lichens of Western Asia