Cladonia lichexanthonica is a species of saxicolous (rock-dwelling) squamulose lichen in the family Cladoniaceae.

The species was formally described as new to science in 2018 by the 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 elevation between 1,050 and 1,140 m (3,440 and 3,740 ft); here the lichen was found growing on siliceous sandstone rock in a transitional forest.

The specific epithet lichexanthonica refers to the presence of lichexanthone, a secondary compound that was not previously known to occur in genus Cladonia.

Since then, its known range has expanded considerably, having been recorded from the states of Minas Gerais, Paraná,[3] Sergipe,[4] and Rio de Janeiro.