| Malmidea cineracea | |
|---|---|
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Fungi |
| Division: | Ascomycota |
| Class: | Lecanoromycetes |
| Order: | Lecanorales |
| Family: | Malmideaceae |
| Genus: | Malmidea |
| Species: | M. cineracea |
| Binomial name | |
| Malmidea cineracea Breuss & Lücking (2015) | |
Malmidea cineracea is a little-known species of corticolous (bark-dwelling), crustose lichen in the family Malmideaceae. [1] It is found in Nicaragua.
The lichen was formally described as a new species in 2015 by the lichenologists Othmar Breuss and Robert Lücking. The type specimen was collected by the first author from a Caribbean lowland rainforest in the Indio Maíz Biological Reserve (San Juan River). The name of the species, cineracea, translates to "ash-greyish", and alludes to the colour of the margins of its apothecia. [2]
Malmidea cineracea grows on bark and has a granulose - isidiate texture with a greenish-grey colour, appearing dull on a whitish, fibrous base layer, and is about 150–200 μm thick. The individual granules range from 70 to 150 μm in diameter, and their cortex, which is colourless, measures 10 to 15 μm thick. The photobiont is chlorococcoid , forming spherical or flattened groups of 30 to 60 μm in diameter, and consists of cells 6 to 8 μm in diameter. The medulla of the lichen has a yellowish hue and does not react to a solution of potassium hydroxide (K−). [2]
The apothecia, or fruiting bodies, are sessile and range from 0.5 to 1.1 mm in diameter and 0.20 to 0.35 mm in height. They are typically rounded but can be slightly irregular, with a flat disc that is grey-brown to brown. The margin is smooth, pale brownish grey, distinct but not prominently raised, and about 0.1 mm wide. The excipulum is compact, with a hyaline outer layer (10–30 μm) and an inner layer densely encrusted with yellowish-brown granules , which turn pale greenish-yellow when treated with potassium hydroxide. The subhymenium is 10–20 μm high and brownish, while the hypothecium is dark brown to brownish black, 100–150 μm deep, and does not react to potassium hydroxide. The hymenium is approximately 80 μm high, hyaline, and turns blue when stained with iodine; it contains simple paraphyses that are not thickened at the tips. The asci are narrowly clavate (club-shaped), measuring 60–70 by 12–16 μm, with a thickened apical wall but no visible internal structure. There are typically 6 to 8 ascospores per ascus, measuring 12–15 by 6–8 μm, ellipsoidal with somewhat pointed ends, and surrounded by a halo that is 0.5–1.0 μm thick. [2]
No conidiomata have been observed to occur in this species, and thin-layer chromatography reveals no substances except for thin bands of terpenoids, likely originating from the bark. Standard chemical spot tests on the thallus and excipulum are all negative. [2]
Malmidea cineracea is similar to Malmidea furfurosa , but can be distinguished by its pale apothecial margins (as opposed to black in M. furfurosa), an excipulum that contains crystals but no medullary tissue, and a yellowish medulla. [2]
Malmidea attenboroughii , which also has a granulose-isidiate thallus, bears a morphological resemblance to Malmidea cineracea. The former species, found in the Amazon rainforest of Bolivia, can be distinguished by its abraded margin, which internally contains yellowish-brown granules that are unreactive when treated with potassium hydroxide (K−). [3]
Malmidea cineracea has been exclusively observed growing on the bark of trees in a lowland rainforest, with its presence limited to Nicaragua. [2] It is one of five Malmidea species that occur in that country. [4]
Ampliotrema cocosense is a little-known species of corticolous (bark-dwelling) lichen in the family Graphidaceae. Found in Cocos Island, Costa Rica, it was described as new to science in 2011. Its distinctive features include its large, muriform ascospores and a notable chemical composition.
Malmidea is a genus of crustose lichens and the type genus of the family Malmideaceae. It was established in 2011 to contain a phylogenetically distinct group of species formerly placed in the genus Malcolmiella. The crust-like thallus of Malmidea lichens has a surface that varies from smooth to rough, featuring textures such as verrucose (wart-like), granulose (grainy), or pustulate (pimpled). These textures are often formed by goniocysts, which are spherical clusters of green algal cells from the family Chlorococcaceae, encased in fungal hyphae. Malmidea comprises nearly 70 mostly tropical species that grow on bark, although a few grow on leaves.
Malmidea attenboroughii is a species of corticolous (bark-dwelling), crustose lichen in the family Malmideaceae. It is known to occur from a single location in the Amazon rainforest of Bolivia.
Thelotrema lueckingii is a species of corticolous (bark-dwelling) crustose lichen in the family Graphidaceae. Found in the laurel forests of Madeira, it was formally described as a new species in 2013 by Othmar Breuss. The species epithet honours German lichenologist Robert Lücking.
Pertusaria albineoides is a species of corticolous (bark-dwelling), crustose lichen in the family Pertusariaceae. Found on the Galápagos Islands, it was formally described as a new species in 2015 by Frank Bungartz, A.W.Archer, Alba Yánez-Ayabaca, and John Elix. The type specimen was collected on Alcedo Volcano at an altitude of 1,089 m (3,573 ft), where it was found growing on a partially shaded, rain- and wind-exposed trunk of Scalesia microcephala. The species epithet refers to the similarity to the species Pertusaria albinea, from which it differs by having thin-walled ellipsoid-shaped ascospores that are longer and narrower.
Fissurina amyloidea is a little-known species of script lichen in the family Graphidaceae. It is found in the primary rainforests of Rondônia, Brazil. It is characterized by its weakly carbonizedlirellae and thick-walled, strongly amyloid ascospores. Despite its superficial similarity to Fissurina subfurfuracea, F. amyloidea exhibits unique anatomical features that set it apart from other species within the genus.
Coenogonium flammeum is a species of corticolous (bark-dwelling), crustose lichen in the family Harpidiaceae. It is found in Argentina.
Megalospora galapagoensis is a species of corticolous (bark-dwelling), crustose lichen in the family Megalosporaceae. It is endemic to the Galápagos Islands. The lichen has a yellowish grey to whitish grey, glossy, and thick thallus that can grow up to 20 cm in diameter and has soredia evolving from coarse, corticated granules into confluent formations. Its apothecia are round, grey-black to black, and glossy.
Lecanactis malmideoides is a little-known species of corticolous (bark-dwelling), crustose lichen in the family Roccellaceae. First described in 2018, it is found in Brazil. Characteristics of the lichen include its pruinosediscs, thin and glossy black margins, and ascospore structure.
Malmidea albomarginata is a species of corticolous (bark-dwelling), crustose lichen in the family Malmideaceae. It is found in Venezuela.
Malmidea allobakeri is a species of corticolous (bark-dwelling), crustose lichen in the family Malmideaceae. It is found in Venezuela.
Malmidea allopapillosa is a species of corticolous (bark-dwelling), crustose lichen in the family Malmideaceae. It is found in Venezuela.
Malmidea atlanticoides is a little-known species of corticolous (bark-dwelling), crustose lichen in the family Malmideaceae. It is found in Brazil.
Malmidea hechicerae is a species of corticolous (bark-dwelling), crustose lichen in the family Malmideaceae. It is found in Venezuela.
Malmidea hernandeziana is a little-known species of corticolous (bark-dwelling), crustose lichen in the family Malmideaceae. It is found in Venezuela. The distinctive features of this species include a thallus with coralloid-like outgrowths, light-coloured fruiting bodies (ascomata) with a specialised structural layer, relatively large spores that tend to have slightly thickened walls at their ends, and the absence of specific lichen products typically found in other species of the genus. This combination of characteristics sets Malmidea hernandeziana apart from other species in the genus Malmidea.
Malmidea isidiifera is a species of corticolous (bark-dwelling), crustose lichen in the family Malmideaceae. It is found in Brazil and Venezuela.
Malmidea leucopiperis is a species of corticolous (bark-dwelling), crustose lichen in the family Malmideaceae. It is found in Brazil.
Malmidea rhodopisoides is a species of corticolous (bark-dwelling), crustose lichen in the family Malmideaceae. It is found in Brazil.
Malmidea subcinerea is a species of corticolous (bark-dwelling), crustose lichen in the family Malmideaceae. It is found in Venezuela. The lichen has a smooth, dull thallus varying in colour from grey to olive, with a white internal medulla. It has sessile, rounded apothecia with light beige to greyish-brown discs.
Malmidea volcaniana is a species of corticolous (bark-dwelling), crustose lichen in the family Malmideaceae. It is found in Venezuela. A major characteristic of the species is the coralloid (coral-shaped) clumps of isidia-like outgrowths on the thallus surface.
