# Marcelaria

> Mediated Wiki article. Canonical URL: https://mediated.wiki/source/Marcelaria
> Markdown URL: https://mediated.wiki/source/Marcelaria.md
> Source: https://en.wikipedia.org/wiki/Marcelaria
> Source revision: 1352385615
> License: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/)

***Marcelaria*** is a [genus](/source/Genus) of [crustose lichens](/source/Crustose_lichen) in the family [Trypetheliaceae](/source/Trypetheliaceae).[1] It has three species.[2] These lichens grow as crusty patches on tree bark and are recognised by their bright orange, yellow, or red colouring. They produce distinctive flask-shaped [fruiting bodies](/source/Fruiting_bodies) that are vividly pigmented and sit directly on the lichen's surface. The genus is found mainly in [tropical](/source/Tropical) regions of Asia, Africa, and the Americas.

## Taxonomy

The genus was [circumscribed](/source/Circumscription_(taxonomy)) in 2013 by [André Aptroot](/source/Andr%C3%A9_Aptroot), Matthew P. Nelsen, and Sittiporn Parnmen, with *[Marcelaria purpurina](/source/Marcelaria_purpurina)* assigned as the [type species](/source/Type_species). The genus contains species that were previously in the *[Laurera](/source/Laurera) purpurina* [species complex](/source/Species_complex). Species in *Marcelaria* contain [secondary compounds](/source/Secondary_metabolite) such as red, orange, and yellow [anthraquinones](/source/Anthraquinone), and sometimes [lichexanthone](/source/Lichexanthone). The genus name honours Brazilian lichenologist Marcela Cáceres.[3]

In 2016, Aptroot and Nepi made a formal proposal to [conserve](/source/Conserved_name) the name *Marcelaria* over *Buscalionia*. This decision was necessitated by the rediscovery of type material originally described in 1940 by [Maria Cengia Sambo](/source/Maria_Cengia_Sambo) as *Buscalionia rubra*,[4] which technically should take [priority](/source/Principle_of_priority) as per the [rules of botanical nomenclature](/source/International_Code_of_Nomenclature_for_algae,_fungi,_and_plants). Given the widespread recognition and use of the name *Marcelaria*, especially for the type species *M. purpurina*, the authors advocated for its conservation to maintain clarity and consistency in lichenological studies.[5] The proposal was rejected by the Nomenclature Committee for Fungi in 2023, who noted that the authors missed a critical 1953 annotation that identified the type of *Buscalionia* (*B. rubra*) as [conspecific](/source/Conspecific) with *Laurera purpurina*, a species central to *Marcelaria*. Considering this oversight, the relatively short period during which *Marcelaria* had been used, and the fact that only three [new combinations](/source/New_combination) would be required if *Buscalionia* were adopted instead, the committee recommended against the conservation of *Marcelaria*.[6]

## Description

*Marcelaria* forms a crust-like [thallus](/source/Thallus) on tree bark (corticolous). Part of the thallus can sit within the outer bark layer (endoperidermal). The surface "skin" () is thin, firm and slightly cartilage-like, and is built from hyphae arranged like vertical threads (). The [photosynthetic](/source/Photosynthesis) partner is from the [green algal](/source/Green_alga) genus *[Trentepohlia](/source/Trentepohlia_(alga))*.

[Sexual](/source/Sexual_reproduction) fruiting bodies are abundant and —i.e. they resemble tiny, flask-like, single-chambered warts (unilocular) that sit directly on the thallus without a stalk (). They occur singly or in small groups, but do not merge into a larger compound structure (not ). Their outer covering is vividly pigmented in bright orange-yellow to red, and there is usually a visible split between the inner wall of the fruit body and the surrounding covering tissue. This covering is formed mainly by a thick, gelatinised inner that turns green when treated with [potassium hydroxide](/source/Potassium_hydroxide) solution (the standard "K" spot test used by lichenologists).

Inside the fruiting bodies, the jelly-like matrix () contains thin, straight filaments that branch and interconnect () and do not react with iodine (IKI-negative). The [asci](/source/Ascus) have two separable wall layers (), show a broad, flat apical chamber (), are club-shaped with a short stalk, and are also IKI-negative. The spores are colourless, multi-celled with both cross- and longitudinal walls (), oblong-oval to [ellipsoid](/source/Ellipsoid) or spindle-shaped, lack a dominant median [septum](/source/Septum), and have an inner spore wall () with rounded internal spaces (). Asexual structures ([pycnidia](/source/Pycnidia)) have a tiny pore-like opening (a ostiole) and a characteristically brain-like, lobed interior; they produce colourless, rod-shaped [conidia](/source/Conidia). Chemically, species contain several [anthraquinone](/source/Anthraquinone) pigments in red, orange and yellow tones (sometimes concentrated in either the thallus or the fruiting bodies), and [lichexanthone](/source/Lichexanthone) is often present.

## Species

- *[Marcelaria benguelensis](/source/Marcelaria_benguelensis)* – continental southeast Asia
- *[Marcelaria cumingii](/source/Marcelaria_cumingii)* – southeast Asia
- *[Marcelaria purpurina](/source/Marcelaria_purpurina)* – [neotropics](/source/Neotropics); tropical West Africa

## References

1. Wijayawardene, Nalin; Hyde, Kevin; Al-Ani, Laith Khalil Tawfeeq; Somayeh, Dolatabadi; Stadler, Marc; Haelewaters, Danny et al. (2020). "Outline of Fungi and fungus-like taxa". *Mycosphere*. **11**: 1060–1456. [doi:10.5943/mycosphere/11/1/8](https://doi.org/10.5943/mycosphere/11/1/8). [hdl:11336/151990](https://hdl.handle.net/11336/151990)

1. Aptroot, A.; Nelsen, M.P.; Parnmen, S. (2013). ["*Marcelaria*, a new genus for the *Laurera purpurina* group in the Trypetheliaceae (Ascomycota: Dothideomycetes)"](https://archive.org/details/2013_Glalia_5_2). *Glalia*. **5** (2): 1–14.

1. Sambo, M. (1940). "Licheni del Brasile". *Annali di Botanica*. **22**: 19–41.

1. Aptroot, André & Nepi, Chiara (2017). "(2492) Proposal to conserve the name *Marcelaria* against *Buscalionia* (Trypetheliaceae, lichenized Ascomycota)". *Taxon*. **66** (1): 200–201. [doi:10.12705/661.20](https://doi.org/10.12705/661.20)

1. May, Tom W. & Lendemer, James C. (2023). "Report of the Nomenclature Committee for Fungi: 22". *Taxon*. **72** (6): 1356–1363. [doi:10.1002/tax.13099](https://doi.org/10.1002/tax.13099)

---
Adapted from the Wikipedia article [Marcelaria](https://en.wikipedia.org/wiki/Marcelaria) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/Marcelaria?action=history)). Available under [Creative Commons Attribution-ShareAlike 4.0 International](https://creativecommons.org/licenses/by-sa/4.0/). Changes may have been made.