Caprettia lichexanthotricha is a species of lichen in the family Monoblastiaceae. Found in Brazil, it was formally described as a new species in 2021 by lichenologists André Aptroot and Maria Fernanda de Souza. The type specimen was collected by the authors from Tagaçaba (Guaraqueçaba, Paraná); here the lichen was found growing on tree bark. It has a dull, pale greenish-grey thallus that covers an area up to 10abbr=onNaNabbr=on. The photobiont partner of the lichen is trentepohloid, and in some parts of the thallus the resident algae partly escape and become filamentous. The thallus fluoresces a patchy yellow when shone with a UV light, due to the presence of lichexanthone, a secondary chemical for which the lichen is named. Caprettia lichexanthotricha is the only species in genus Caprettia that has lichexanthone.