Austroroccella, a new fruticose genus in the family Roccellaceae

The new genus Austroroccella Tehler & Ertz is described to incorporate one species A. gayana (Mont.) Tehler & Ertz comb. nov. (= Roccella gayana Mont.). Austroroccella gayana is very similar to the fruticose species in Roccellina Darb., as well as to many saxicolous species in the fruticose genus Roccella DC., but differs from these genera by the epruinose dark or black discs and the sole presence of roccellic acid. Molecular data places it in an isolated position with a long branch in the family Roccellaceae in a highly supported clade including the genera Dendrographa Darb., Syncesia Taylor and Roccellina.