| Pyrenula aurantiacorubra | |
|---|---|
Scientific classification  | |
| Kingdom: | Fungi |
| Division: | Ascomycota |
| Class: | Eurotiomycetes |
| Order: | Pyrenulales |
| Family: | Pyrenulaceae |
| Genus: | Pyrenula |
| Species: | P. aurantiacorubra |
| Binomial name | |
| Pyrenula aurantiacorubra Aptroot & M.Cáceres (2014) | |
 Holotype: Serra do Machado, Brazil | |
Pyrenula aurantiacorubra is a species of corticolous (bark-dwelling), crustose lichen in the family Pyrenulaceae. [1] Found in Brazil, this species is characterised by its distinctive orange-red thallus (the main body of the lichen). Its ascospores are muriform , meaning they have multiple chambers, and are 3 (occasionally up to 5) by 1–2-septate, measuring 9–18 μm by 5–10 μm. [2]
The type specimen of Pyrenula aurantiacorubra was collected from Serra do Machado in Ribeirópolis, Sergipe, Brazil, at an elevation of approximately 250 m (820 ft). The thallus is thin, somewhat granular , and orange-red mottled with grey. It lacks pseudocyphellae, which are small pores on the surface, and does not have a prothallus (a border around the thallus). The ascomata (fruiting bodies) are superficial (situated on the surface), globose (roughly spherical), 0.2–0.35 mm in diameter, and generally brown with an orange-red powdery coating, the pruina . The wall of the ascomata is barely carbonised (blackened). The ostiole, or opening, is apical and black. The hamathecium , the tissue between the asci, is not inspersed (does not contain oil droplets). The ascospores are arranged irregularly in the asci, brown, and muriform, with mostly rounded internal cavities. [2]
Pyrenula aurantiacorubra does not have pycnidia (small asexual fruiting bodies). Chemically, the pigment reacts with potassium hydroxide (K+) to produce a deep crimson colour and shows an orange reaction under UV light. Thin-layer chromatography has revealed several anthraquinones (a type of organic compound), including 7-chloroemodin as the major compound, with one or more derivatives as minor compounds. [2]
Pyrenula aurantiacorubra grows on smooth bark in disturbed Atlantic rainforests and is currently only known from Brazil. It is distinguished from other species by its striking orange-red thallus. In the field, it was recognised as a new species due to its distinctive appearance, even before detailed scientific analysis. It is similar to Pyrenula ochraceoflava , which grows in the same location but has a yellow-orange thallus. Unlike P. aurantiacorubra, P. ochraceoflava only contains 7-chloroemodin as its major compound. [2]