''Peltula submarginata'' 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, giv ...

(rock-dwelling),

squamulose lichen A squamulose lichen is a lichen that is composed of small, often overlapping "scales" called squamules. If they are raised from the substrate Substrate may refer to: Physical layers *Substrate (biology), the natural environment in which an o ...

in the family

Peltulaceae The Peltulaceae are a family of ascomycete fungi A fungus (plural, : fungi or funguses) is any member of the group of Eukaryote, eukaryotic organisms that includes microorganisms such as yeasts and Mold (fungus), molds, as well as the mor ...

, first described in 2022. It occurs in China.

Taxonomy

''Peltula submarginata'' was formally identified and named by Qiuxia Yang and Xinli Wei in 2022. Its

species epithet Specific name may refer to: * in Database management systems, a system-assigned name that is unique within a particular database In taxonomy, either of these two meanings, each with its own set of rules: * Specific name (botany) A botanical name ...

suggests a close morphological similarity to '' Peltula marginata'' but with distinct differences noted in its physical and reproductive structures. The

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of seve ...

was collected in Beijing's Dayangshan National Forest Park at an elevation of , where it was found growing on soil on the surface of a rock.

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 ...

of ''Peltula submarginata'' is saxicolous, meaning it grows on rocks, and has a -subfruticose form—appearing scale-like initially and developing a stalk or -like attachment to the . of the thallus are circular to elliptical, up to 2 mm in diameter, with a top that is almost flattened. The margin is entire, and the upper surface is yellowish olive with a black-brown border, smooth, and lacks a powdery covering (). The thallus thickness ranges between 230 and 370

micrometre 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 ...

s (μm), without a developed cortex but featuring a protective yellowish . The is substantial, encircling the perimeter of the squamules, and 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 ...

contains sparse

hypha A hypha (; ) is a long, branching, filamentous structure of a fungus, oomycete, or actinobacterium. In most fungi, hyphae are the main mode of vegetative growth, and are collectively called a mycelium. Structure A hypha consists of one o ...

e with significant hollow areas, providing structure and perhaps nutrient storage. Reproductive structures include

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 ...

(fruiting bodies), numbering 1 to 7 per lobe, immersed within the thallus and black when mature. 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 som ...

, or spore-producing layer, is light yellow and up to 215 μm tall, with spores being released through asci that are to in shape and contain more than 100 spores each.

Habitat and distribution

''Peltula submarginata'' is typically found on sun-exposed

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 ...

faces, predominantly in areas where other lichens are absent, suggesting a specific ecological niche. At the time of its original publication, it was only known to occur in its

type locality Type locality may refer to: * Type locality (biology) * Type locality (geology) See also * Local (disambiguation) * Locality (disambiguation) {{disambiguation ...

in China.

References

{{Taxonbar, from=Q130703200 Lichinomycetes Lichen species Lichens described in 2022 Lichens of China