''Flavoplaca arcisproxima'' is a species of saxicolous (rock-dwelling), 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 primarily in the coastal regions of the Crimean Peninsula and the eastern Mediterranean, particularly in Crete, Greece.

Taxonomy

The lichen was formally described in 2009 by the lichenologists Jan Vondrák, Jan Říha, Ulf Arup, and Ulrik Søchting. The species is named ''arcisproxima'', meaning "close to arcis", reflecting its phylogenetic and morphological similarity to '' Caloplaca arcis''. The taxon was transferred 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-informed restructuring of the family

Description

The thallus of ''Flavoplaca arcisproxima'' is coloured yellow to yellow-orange, comprising solitary or rarely aggregated, somewhat . These squamules are flat, smooth, and have margins divided into minute . They are typically 80 to 240

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 0.44 to 1.18 mm wide. The marginal

soralia Soredia are common reproductive structures of lichens. Lichens reproduce asexually by employing simple fragmentation and production of soredia and isidia. Soredia are powdery propagules composed of fungal hyphae wrapped around cyanobacteria o ...

are of the ''confusa'' or ''flavocitrina'' type, with soredia or measuring between 25 and 86 μm in diameter. The species lacks a distinct , but has an (honeycombed) cortex with a thickness ranging from 8 to 46 μm. Apothecia were absent in the initial specimens of ''Flavoplaca arcisproxima'' investigated. They were found in some specimens collected in Ukraine.

Conidia A conidium ( ; ), sometimes termed an asexual chlamydospore or chlamydoconidium (), is an asexual, non-motile spore of a fungus. The word ''conidium'' comes from the Ancient Greek word for dust, ('). They are also called mitospores due to the ...

are quite small, with measurements ranging from 2.5 to 4.0 μm in length and 0.5 to 1.5 μm in width.

Distribution and ecology

''Flavoplaca arcisproxima'' is known from maritime sites, usually in the

supralittoral zone The supralittoral zone, also known as the splash zone, spray zone or the supratidal zone, sometimes also referred to as the white zone, is the area above the spring high tide line, on coastlines and estuaries, that is regularly splashed, but not su ...

. It prefers base-rich, hard

siliceous rock Siliceous rocks are sedimentary rocks that have silica (SiO2) as the principal constituent. The most common siliceous rock is chert; other types include diatomite. They commonly form from silica-secreting organisms such as radiolarians, diatoms, or ...

s, such as

diabase Diabase (), also called dolerite () or microgabbro, is a mafic, holocrystalline, subvolcanic rock equivalent to volcanic basalt or plutonic gabbro. Diabase dikes and sills are typically shallow intrusive bodies and often exhibit fine-graine ...

, and can also be found on lime-rich

claystone Mudrocks are a class of fine-grained siliciclastic sedimentary rocks. The varying types of mudrocks include siltstone, claystone, mudstone, slate, and shale. Most of the particles of which the stone is composed are less than and are too sm ...

. The species is found accompanying several other lichen species, including ''Caloplaca'' cf. ''aegea'', ''

Calogaya biatorina ''Calogaya'' is a genus of lichen-forming fungi belonging to the family Teloschistaceae. It has 19 species. The genus was circumscription (taxonomy), circumscribed in 2013 by Ulf Arup, Ulrik Søchting, and Patrik Frödén. The generic name ''Cal ...

'', ''Caloplaca'' aff. ''furax'', '' Kuettlingeria teicholyta'', '' Candelariella plumbea'', '' C. vitellina'', ''

Catillaria chalybeia ''Catillaria'' is a genus of crustose lichens in the family Catillariaceae. The genus was circumscribed by Italian lichenologist Abramo Bartolommeo Massalongo in 1852. It is the type genus of Catillariaceae, which was circumscribed by Austrian ...

'', ''

Diplotomma alboatrum ''Diplotomma alboatrum'' is a species of lichen in the family Caliciaceae. It was first described as ''Lichen alboater'' by German lichenologist Georg Franz Hoffmann in 1784. Julius von Flotow transferred it to the genus ''Diplotomma ''Diplot ...

'', '' Polyozosia albescens'', '' Polyozosia dispersa'', ''

Phaeophyscia orbicularis ''Phaeophyscia'' is a genus of lichen-forming fungi in the family Physciaceae. Species *''Phaeophyscia adiastola'' *'' Phaeophyscia cernohorskyi'' *'' Phaeophyscia ciliata'' *'' Phaeophyscia confusa'' *'' Phaeophyscia constipata'' *'' Ph ...

'', '' Verrucaria macrostoma'' f. ''furfuracea'', and '' Xanthoria'' cf. ''calcicola''. The species is known from the Black Sea region of the Crimean Peninsula and Crete in the eastern Mediterranean.

References

{{Taxonbar, from=Q25637580, from2=Q10440406 arcisproxima Lichen species Lichens of Europe Lichens described in 2009 Taxa named by Ulf Arup Taxa named by Ulrik Søchting