Gyalideopsis macarthurii

Gyalideopsis macarthurii is a species of corticolous (bark-dwelling) crustose lichen in the family Gomphillaceae. The pale greenish-grey lichen forms thin, shiny crusts on bark and rotting logs in montane cloud forest environments, particularly in exposed areas along forest edges and pastures, and has been documented in Costa Rica, Florida, and Brazil. It is distinguished by its distinctive fruiting bodies with thin triangular lobes covering the margins, extremely small specialized reproductive structures called hyphophores, and its habit of growing on bark rather than leaves, which separates it from its closest relative, Gyalideopsis lobulata....read more on Wikipedia.