Cladonia lichexanthonica

Cladonia lichexanthonica is a rare species of saxicolous (rock-dwelling) lichen in the family Cladoniaceae. Found in Bahia, Brazil, it was formally described as a new species in 2018 by lichenologists André Aptroot and Marcela Eugenia da Silva Cáceres. The type specimen was collected by the authors from the Morro do Pai Inácio (in Chapada Diamantina National Park) at an altitude between 1050 and 1140 m; here the lichen was found growing on siliceous sandstone rock in a transitional forest. Cladonia lichexanthonica is only known to occur at the type locality (part of the Chapada Diamantina mountains), and is only known from the type specimen. The lichen has a squamulose (scaley) thallus measuring up to 10 cm in diameter; this consists of a 5 mm thick crust comprising individual crowded squamules, pale-olive green to olive brown, measuring 1–5 mm in size. The specific epithet lichexanthonica refers to the presence of lichexanthone, a secondary compound that was not previously known to occur in genus Cladonia.