| Pyrenula albonigra | |
|---|---|
Scientific classification  | |
| Kingdom: | Fungi |
| Division: | Ascomycota |
| Class: | Eurotiomycetes |
| Order: | Pyrenulales |
| Family: | Pyrenulaceae |
| Genus: | Pyrenula |
| Species: | P. albonigra |
| Binomial name | |
| Pyrenula albonigra Aptroot, D.S.Andrade & M.Cáceres (2014) | |
 Holotype: Refúgio de Vida Silvestre Mata do Junco, Brazil | |
Pyrenula albonigra is a species of corticolous (bark-dwelling), crustose lichen in the family Pyrenulaceae. [1] Found in Brazil, this species is notable for its pale grey, somewhat glossy thallus (the main body of the lichen) that also covers the ascomata (fruiting bodies), except for a prominent black opening (ostiole). The ascospores are 3-septate, meaning they are divided into four sections, and measure 17–20 μm by 7–9 μm. [2]
The type specimen of Pyrenula albonigra was collected from the Mata do Junco Wildlife Refuge in Sergipe, Brazil, at an elevation of 150 m (490 ft). The thallus is thin, mineral grey, and lacks tiny pores called pseudocyphellae. It is bordered by a black line (a prothallus) up to 1 mm wide. The ascomata are superficial, hemispherical, 0.3–0.4 mm in diameter, and covered by the thallus except for a wide black area around the ostiole. The wall of the ascomata is carbonised (blackened) all around. The hamathecium , a layer of tissue in the ascomata, does not contain oil droplets. The ascospores are brown, irregularly arranged in the asci, and have diamond-shaped inner cavities separated from the wall by a thick layer. [2]
Pyrenula albonigra does not show any reaction under ultraviolet light, and no lichen products were detected using thin-layer chromatography. It grows on smooth bark in undisturbed Atlantic rainforests and is only known to occur in Brazil. [2]