Arthonia parietinaria – A common but frequently misunderstood lichenicolous fungus on species of the Xanthoria parietina-group.

Arthonia parietinaria is described as new to science. Host of the type and at the same time the only confirmed host species is the foliose macrolichen Xanthoria parietina . Sequence data of nucLSU rRNA genes reveal a close relationship to Arthonia molendoi . A. parietinaria is recorded for many countries in Europe, western Asia, and northern Africa. [ABSTRACT FROM AUTHOR]