| Byssoloma xanthonicum | |
|---|---|
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Fungi |
| Division: | Ascomycota |
| Class: | Lecanoromycetes |
| Order: | Lecanorales |
| Family: | Pilocarpaceae |
| Genus: | Byssoloma |
| Species: | B. xanthonicum |
| Binomial name | |
| Byssoloma xanthonicum Aptroot (2014) | |
Byssoloma xanthonicum is a species of corticolous (bark-dwelling), crustose lichen in the family Pilocarpaceae. [1] It is found in New Caledonia.
The lichen was formally described by the Dutch lichenologist André Aptroot in 2014. The type specimen was collected near Farino in New Caledonia, at an elevation of about 300 m (980 ft). Byssoloma xanthonicum is one of the few corticolous species within the genus Byssoloma . [2]
Byssoloma xanthonicum has a thin, non- corticate (without a cortex), and continuous thallus (the main body of the lichen) that is cream-coloured with a dull appearance. It is bordered by a thin brown line known as the prothallus . The algae within the thallus are chlorococcoid (green and spherical). The species features sessile (directly attached) apothecia, which are the fruiting bodies, measuring 0.2–0.6 mm in diameter. These apothecia are round but often lobate (lobed) in shape, with a flat, dull, dark brown disc that is not pruinose (powdery). The margin surrounding the disc is cream to chamois-coloured, dull, and has a felty texture, approximately 0.05 mm wide. The hymenium (spore-bearing layer) is 25–35 μm high, hyaline (translucent) but becomes brownish at the base due to diluted pigment from the hypothecium . The paraphyses (sterile filaments in the hymenium) are branched. The hypothecium (tissue beneath the hymenium) is dark brown, coloured by a concentrated pigment. The excipulum (outer layer of the apothecia) is hyaline and composed of anastomosing (interconnecting) hyphae approximately 3 μm wide. The ascus (spore-bearing cell) is of the Pilocarpaceae-type, with a tholus (central part) that reacts pale blue to iodine-potassium iodide (IKI) staining and has a darker blue tube inside. Each ascus contains 8 ascospores . These spores are hyaline, fusiform (spindle-shaped), 3-septate (having three divisions), measuring 11–13 by 2.5–3.5 μm, and are slightly constricted at the septa (divisions). Pycnidia (asexual reproductive structures) were not observed in this species. [2]
The thallus of Byssoloma xanthonicum fluoresces a yellow-orange colour when lit with a ultraviolet light, owing to the presence of the compound lichexanthone. It additionally has a K+ (yellow-red) reaction, a result of norstictic acid. [2]
Byssoloma xanthonicum bears a resemblance in thallus and apothecium colour to B. chlorinum . However, it differs significantly in its chemical composition, most notably demonstrated by its strong UV+ (yellow-orange) reaction. Xanthones, a type of chemical compound, are known in Byssoloma, notably in B. meadii . Compared to B. meadii, Byssoloma xanthonicum stands out due to its pale hypothecium and is more similar in colour and appearance to B. leucoblepharum . [2]
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.
Pertusaria cerroazulensis 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, Alan W. Archer, Alba Yánez-Ayabaca, and John Elix. The type specimen was collected from the Cerro Azul volcano at an altitude of 1,038 m (3,406 ft), where in a small, shaded woodland, it was growing on twigs of Psidium galapageium. The species epithet refers to the type locality.
Calopadia saxicola is a species of saxicolous (rock-dwelling) crustose lichen in the family Pilocarpaceae. It is found on the rocky shores of southern Brazil, where it thrives in the shade of vegetated zones and grows directly on rocks away from other crustose lichens. The lichen was formally described as a new species in 2015. Calopadia saxicola stands out from its close relatives due to its well-defined thallus, reddish-brown disc, thicker hymenium, and smaller conidia.
Enterographa rotundata is a species of corticolous (bark-dwelling) crustose lichen in the family Roccellaceae. This species was discovered in Brazil, growing on the smooth bark of trees in the Brazilian Caatinga forest. It has round apothecia, a feature that sets it apart from most of its kind.
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.
Pyrrhospora palmicola is a species of corticolous (bark-dwelling), crustose lichen in the family Lecanoraceae. It has a yellow thallus with rounded to irregular apothecia with pale brown or black discs. The lichen is found in Mato Grosso, Brazil, and the Seychelles.
Coenogonium flammeum is a species of corticolous (bark-dwelling), crustose lichen in the family Harpidiaceae. It is found in Argentina.
Megalospora austropacifica is a species of corticolous (bark-dwelling), crustose lichen in the family Megalosporaceae. It is found on the islands of Taveuni and Viti Levu in Fiji. It has a yellowish grey to whitish grey, glossy thallus that is thick and may appear slightly wrinkled or smooth, often with irregular cracks and small papillae containing conidiomata, but lacking isidia and soredia. Its apothecia are circular, up to 4.5 mm in diameter, with the disc evolving from concave to slightly convex and coloured from orange-brown to red-brown, surrounded by a thick, prominent margin.
Rinodina densisidiata is a little-known species of corticolous (bark-dwelling), crustose lichen in the family Physciaceae, first described in 2018. Found in Brazil, it is characterised its dense layer of cylindrical isidia and unique ascospore characteristics.
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 leucopiperis 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.
Enterographa aldabrensis is a species of corticolous (bark-dwelling), crustose lichen in the family Roccellaceae. It is only known to occur in Aldabra in the Seychelles.