# Neoplaca > Mediated Wiki article. Canonical URL: https://mediated.wiki/source/Neoplaca > Markdown URL: https://mediated.wiki/source/Neoplaca.md > Source: https://en.wikipedia.org/wiki/Neoplaca > Source revision: 1293573473 > License: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) ***Neoplaca*** is a fungal [genus](/source/Genus) in the family [Teloschistaceae](/source/Teloschistaceae).[1] It comprises the single species ***Neoplaca mirabilis***, a [ground-dwelling](/source/Terricolous_lichen), [crustose lichen](/source/Crustose_lichen). Both the genus and species were described in 2023 from specimens collected in [Yakutia](/source/Yakutia), Russia. The species is distinctive among its relatives for its whitish to greyish (scaly) [thallus](/source/Thallus) with contrasting [citrine](/source/Citrine_(colour)) to orange-yellow , and for lacking the [anthraquinone](/source/Anthraquinone) pigments typical of its family. Instead, it produces [naphthopyran](/source/Naphthopyran) compounds, making it the first known case of these compounds in the Teloschistaceae. The species grows on base-rich soil on exposed south-facing siliceous outcrops, where it is locally common but known only from two localities along the [Eastern Khandyga](/source/Eastern_Khandyga) River in Yakutia. ## Taxonomy Both the genus *Neoplaca* and its single species were described as new in 2023 by the lichenologists Ivan Frolov, Ilya Prokopiev, and Liudmila Konoreva. The genus name *Neoplaca* combines the prefix *neo*- (new) with -*placa*, referencing *[Caloplaca](/source/Caloplaca)*, a related genus in the [Teloschistaceae](/source/Teloschistaceae). [Molecular phylogenetics](/source/Molecular_phylogenetics) analysis places *Neoplaca* within the subfamily Caloplacoideae. It forms a distinct [lineage](/source/Lineage_(evolution)) that has a [sister](/source/Sister_group) to 'Caloplaca conversa' [auct.](/source/Auct.) (not *C. conversa* sensu [Krempelhuber](/source/August_von_Krempelhuber)) within a well-supported [clade](/source/Clade) that includes the genera *[Kuettlingeria](/source/Kuettlingeria)*, *[Lendemeriella](/source/Lendemeriella)*, and *[Pyrenodesmia](/source/Pyrenodesmia)*. Despite its unusual chemistry and morphology for the family, [DNA sequence](/source/DNA_sequence) data firmly establishes its position within the Teloschistaceae.[2] The genus is [monotypic](/source/Monotypic), containing only the [type species](/source/Type_species) *Neoplaca mirabilis*. The [specific epithet](/source/Botanical_name) *mirabilis* ([Latin](/source/Latin) for "remarkable" or "wonderful") refers to the species' unique chemical and morphological characteristics within the Teloschistaceae. The [holotype](/source/Holotype) specimen (LE L-21846) was collected in Russia, [Republic of Sakha](/source/Republic_of_Sakha) (Yakutia), [Tomponsky District](/source/Tomponsky_District), along the [Eastern Khandyga](/source/Eastern_Khandyga) river. The type collection includes DNA sequence data for three [genetic markers](/source/Genetic_marker): [nrITS](/source/Internal_transcribed_spacer), nrLSU, and [mtSSU](/source/Mitochondrial_DNA).[2] ## Description *Neoplaca mirabilis* forms a distinctive crust-like growth ([thallus](/source/Thallus)) composed of scattered scale-like structures () that are typically whitish to greyish in colour, though occasionally showing a pale yellow tint. These squamules measure 1–4.5 mm across and 0.3–1 mm in thickness. As they develop, they begin as tiny about 0.1 mm wide, which then grow into small convex structures and finally mature into fully formed squamules. These mature squamules often display an intricate pattern of wide, winding folds on their surface that resembles brain tissue.[2] The squamules can grow individually or overlap like roof tiles. In some cases, they merge to form larger, patterned patches up to 1 cm across. A distinctive feature of the species is its method of [vegetative reproduction](/source/Vegetative_reproduction): it produces small, round structures called along the edges of the squamules. These blastidia are [citrine](/source/Citrine_(colour)) to orange-yellow in colour, creating a marked contrast with the paler squamules. Mature squamules are often surrounded by numerous tiny new growths, which likely develop from these blastidia, suggesting the species reproduces effectively through these structures. No other reproductive structures ([apothecia](/source/Apothecia) or [pycnidia](/source/Pycnidia)) have been observed.[2] When viewed in cross-section, *N. mirabilis* reveals several distinct layers. The outer protective layer () is 33–40 [μm](/source/%CE%9Cm) thick and consists of two distinct parts: a lower colourless layer and an upper layer containing cells with brown pigment. A white, powdery coating () covers the cortex. Below the cortex lies a layer of algal cells (), 5583 μm thick, while the inner layer (medulla) is white and loosely structured, ranging from 0.2–0.8 mm thick.[2] Unlike most members of its family, which produce orange-red pigments called [anthraquinones](/source/Anthraquinone), *N. mirabilis* contains different chemical compounds. It produces [simonyellin](/source/Simonyellin) as its major [metabolite](/source/Secondary_metatobile), with trace amounts of [consimonyellin](/source/Consimonyellin), as well as an unidentified brown pigment with some characteristics similar to [melanin](/source/Melanin). These pigments are found inside the cells rather than on their surface, which is unusual for lichens in this family. When tested with [potassium hydroxide](/source/Potassium_hydroxide) solution (K), the lichen turns orange-brown, and with [*para*-phenylenediamine](/source/Para-phenylenediamine) (P), it briefly turns yellow.[2] ## Habitat and distribution *Neoplaca mirabilis* is known only from two nearby localities in the Republic of Sakha (Yakutia) in eastern Siberia, Russia. Both sites are situated along the Eastern Khandyga river, where the species grows at elevations between 550 and 850 metres above sea level.[2] The species grows on base-rich soil that covers exposed south-facing [siliceous](/source/Siliceous) rock [outcrops](/source/Outcrop). These outcrops are located along small brooks that cut through the landscape. While the surrounding valley slopes are forested with *[Larix gmelinii](/source/Larix_gmelinii)* (Dahurian larch), the brook valleys themselves remain treeless, likely due to periodic flooding that prevents tree establishment. In its limited known habitat, *N. mirabilis* is relatively common and grows alongside other [soil-dwelling lichens](/source/Terricolous_lichen), including species from the genera *[Collema](/source/Collema)*, *[Endocarpon](/source/Endocarpon)*, *[Leptogium](/source/Leptogium)*, and *[Toninia](/source/Toninia)*.[2] ## References 1. Hyde, K.D.; Noorabadi, M.T.; Thiyagaraja, V.; He, M.Q.; Johnston, P.R.; Wijesinghe, S.N. et al. (2024). ["The 2024 Outline of Fungi and fungus-like taxa"](https://www.researchgate.net/publication/385939154). *Mycosphere*. **15** (1): 5146–6239 [5259]. [doi:10.5943/mycosphere/15/1/25](https://doi.org/10.5943/mycosphere/15/1/25). [hdl:1854/LU-8660838](https://hdl.handle.net/1854/LU-8660838) 1. Frolov, Ivan V.; Prokopiev, Ilya A.; Konoreva, Liudmila A. (2023). ["*Neoplaca mirabilis*, a new genus and a new epigaeic species containing naphthopyrans from the family Teloschistaceae"](https://www.researchgate.net/publication/376007458). *The Lichenologist*. **55** (6): 443–450. [Bibcode:2023ThLic..55..443F](https://ui.adsabs.harvard.edu/abs/2023ThLic..55..443F). [doi:10.1017/S0024282923000567](https://doi.org/10.1017/S0024282923000567) --- Adapted from the Wikipedia article [Neoplaca](https://en.wikipedia.org/wiki/Neoplaca) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/Neoplaca?action=history)). Available under [Creative Commons Attribution-ShareAlike 4.0 International](https://creativecommons.org/licenses/by-sa/4.0/). Changes may have been made.