Pyrenula albonigra

Pyrenula albonigra is a species of corticolous (bark-dwelling), crustose lichen in the family Pyrenulaceae. 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. 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 dr......read more on Wikipedia.