''Pyrenula rubrolateralis'' is a species of corticolous (bark-dwelling), crustose lichen in the family

Pyrenulaceae The Pyrenulaceae are a family of fungi in the order Pyrenulales. The family was first named by German botanist Gottlob Ludwig Rabenhorst in 1870. Species in the family have a widespread distribution, but are especially prevalent in the tropics, wh ...

. Found in Brazil, this species is distinguished by its eccentric (not centrally positioned) red

ostiole An ''ostiole'' is a small hole or opening through which algae or fungi release their mature spores. The word is a diminutive of "ostium", "opening". The term is also used in higher plants, for example to denote the opening of the involuted ...

s (the openings of the fruiting bodies). Its are 3- septate, meaning they are divided into four sections, and measure 20–24

μm The micrometre ( international spelling as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American spelling), also commonly known as a micron, is a unit of length in the International System of Unit ...

by 8–10 μm. The type specimen of ''Pyrenula rubrolateralis'' was collected from Mata do Crasto in

Santa Luzia do Itanhy Santa Luzia do Itanhy is a municipality located in the Brazilian state of Sergipe. Its population was 14,121 (2020) and its area is 330 km2.IBGE The Brazilian Institute of Geography and Statistics ( pt, Instituto Brasileiro de Geografia e Esta ...

, Sergipe, Brazil, at an elevation of approximately . The thallus (the main body of the lichen) is thin, up to 0.1 mm thick, and olive green, following the cracks and fissures in the bark. It lacks

pseudocyphella Pseudocyphellae (singular ''pseudocyphella'') are structures in lichens that appear as tiny pores on the outer surface (the cortex of the lichen. They are caused when there is a break in the cortex of the lichen, and the medullary hyphae extend t ...

e (tiny pores on the surface) and is bordered by a black (a border around the thallus) about 1 mm wide. The ascomata (fruiting bodies) are immersed in the raised areas of the bark and almost completely covered by the thallus. They are (pear-shaped), 0.6–0.9 mm in diameter, and single. The walls of the ascomata are (blackened) all around. The ostioles are eccentric (off-centre), red-brown to bright red, and can be flush with the surface or distinctly convex. The , the tissue between the asci, does not contain oil droplets. The are brown, irregularly (arranged in two rows), with mostly rounded to somewhat diamond-shaped internal cavities separated from the wall by a thick layer. The ends of the ascospores are pointed. ''Pyrenula rubrolateralis'' does not have pycnidia (small asexual fruiting bodies). Chemically, the ostioles do not react with potassium hydroxide (K–), the thallus does not fluoresce under ultraviolet light, and no substances were detected using thin-layer chromatography. ''Pyrenula rubrolateralis'' grows on smooth bark in undisturbed Atlantic rainforests and is only found in Brazil. This species is characterised by its eccentric red ostioles. It is similar to the North American species '' Pyrenula wetmorei'', which differs by having an hamathecium (containing oil droplets) and ascospores with black pigment bands that obscure the septa.

References

{{Taxonbar, from=Q108308375 rubrolateralis Lichen species Lichens described in 2014 Lichens of Northeast Brazil Taxa named by André Aptroot Taxa named by Marcela Cáceres

See also

References