| Malmidea albomarginata | |
|---|---|
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Fungi |
| Division: | Ascomycota |
| Class: | Lecanoromycetes |
| Order: | Lecanorales |
| Family: | Malmideaceae |
| Genus: | Malmidea |
| Species: | M. albomarginata |
| Binomial name | |
| Malmidea albomarginata Kalb & J.E.Hern.(2021) | |
 | |
| Holotype site: Cerro El Volcán, Venezuela | |
Malmidea albomarginata is a species of corticolous (bark-dwelling), crustose lichen in the family Malmideaceae. [1] It is found in Venezuela.
The lichen was formally described as a new species in 2021 by the lichenologists Klaus Kalb and Jesús Maldonado. The type specimen was collected by the authors from the Cerro El Volcán (Miranda) at an elevation of 1,460 m (4,790 ft); there it was found growing in a disturbed tropical mountain rainforest. The species epithet albomarginata alludes to the distinctive white margins that characterise its apothecia. [2]
Malmidea albomarginata is a crustose lichen with a continuous thallus measuring 200–300 µm in thickness. The thallus surface is initially verrucose , with verrucae being scarce and unevenly distributed, each measuring 0.1–0.3 mm in height and 0.15–0.3 mm in width. Over time, the thallus becomes dull and transforms from grey or greenish-grey to a coralloid granular texture as it ages. This species lacks soralia and isidia. The medulla of both the verrucae and thallus is white to faintly yellow, reacting K+ (orange to reddish) when tested with potassium hydroxide, but without a reaction to the P spot test. The photobiont is chlorococcoid , with cells around 6–8 µm in diameter. [2]
Apothecia in Malmidea albomarginata are sessile and rounded, ranging from 0.8–1.8 mm in diameter and 0.2–0.3 mm in height. The apothecial discs are flat to slightly convex, with colours varying from ochre to light greyish-brown. The excipulum is of the granifera type, entire , thin, and white. The ectal excipulum is hyaline, while the medullary excipulum is whitish to slightly yellowish, filled with opaque, greyish to yellowish granules that partially dissolve in KOH, producing a K+ (orange-red) efflux. The subhymenium is about 25 µm high and hyaline to light brown, while the centrally located hypothecium is 100–150 µm high, narrowing towards the margin and dark brown, showing no reaction to K tests. The epihymenium is indistinct, and the hymenium measures 75–90 µm in height, being hyaline. Asci are sized 65–80 µm by 12–18 µm, containing 6–8 non-septate, halonate , ellipsoid ascospores per ascus, measuring (10–)14 by 6–9 µm, with a halo of 1.5–2 µm. [2]
Chemically, Malmidea albomarginata primarily contains atranorin, alongside several unidentified xantholepinones. It is distinguished from similar species like Malmidea attenboroughii by differences in apothecia size and the presence of atranorin. In comparison with Malmidea aurigera and Malmidea piperina , Malmidea albomarginata features larger apothecia, a paler apothecial disc, and warts that become coralloid granular. [2]
Pseudochapsa lueckingii is a species of corticolous (bark-dwelling), crustose lichen in the family Graphidaceae. It is known only from a single collection in São Paulo, Brazil.
Maronora is a monotypic fungal genus in the family Fuscideaceae. It contains the single species Maronora cyanosora, a corticolous (bark-dwelling) lichen. It is characterised by its distinctive bluish-grey circular soralia on the thallus, Lecanora-like apothecia, and simple, hyaline ascospores.
Lecanactis minutissima is a species of corticolous (bark-dwelling), crustose lichen in the family Roccellaceae. Found in Sri Lanka, the lichen is characterised by its pale ochraceous thallus and sessile apothecia with dark brown discs, covered with thick white granular pruina.
Caloplaca filsonii is a species of corticolous (bark-dwelling), crustose lichen in the family Teloschistaceae. It has a crust-like thallus that is uneven and warty around the edges and more distinctly wart-like in the centre, coloured in shades of grey and brownish-grey near its reproductive structures (apothecia), but lacking a developed prothallus.
Caloplaca haematommona is a little-known species of corticolous (bark-dwelling), lichen in the family Teloschistaceae. It has a very thin, whitish, crust-like thallus dotted with black, spanning about 10–18 mm in width, and apothecia ranging from 0.2 to 0.8 mm in diameter, and becoming yellow-orange to brownish-orange as they mature. The lichen is known only from its type locality in Western Australia.
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.
Malmidea cineracea is a little-known species of corticolous (bark-dwelling), crustose lichen in the family Malmideaceae. It is found in Nicaragua.
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.
Rinodina maronisidiata is a species of corticolous (bark-dwelling), crustose lichen in the family Physciaceae, first described in 2018. Found at high altitudes in the Venezuelan Andes, it is characterised by its unique isidia-covered thallus and specific ascospore morphology.
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.
Allographa hypostictica is a species of saxicolous (rock-dwelling), crustose lichen in the family Graphidaceae, Found in Brazil, it was described as a new species in 2018. Its thallus contains hypostictic acid and its distinctive apothecia and ascospores.