Pyrenula rubroanomala

Pyrenula rubroanomala is a species of corticolous (bark-dwelling), crustose lichen in the family Pyrenulaceae. The species is characterized by its pale, thickened thallus and by clusters of small, black, flask-shaped fruiting bodies that often merge into irregular, rounded patches. A distinctive feature is the thin red pigment layer over these clusters, which turns purple when tested with potassium hydroxide solution. It is known from the type locality in Costa Rica, where it was found growing on tree bark in secondary vegetation in a moist lowland forest zone....read more on Wikipedia.