Dirina is a genus of lichen-forming fungi in the family Roccellaceae.[1] All Dirina species are crustose lichens with a whitish to greyish brown thallus, and live either on rock or on bark–some species can live on both. The partner is a member of the green algal genus Trentepohlia. Most species occur in the Northern Hemisphere, and are generally restricted to coastal habitats, where they may be locally quite common. Erythrin and lecanoric acid are lichen products that usually occur in Dirina species, along with several other unidentified substances.
The genus was circumscribed in 1825 by Elias Magnus Fries. Swedish lichenologist Anders Tehler published a monograph about the genus in 1983. Thirty years later, he and his colleagues revisited Dirina, combining evidence from molecular phylogenetic analysis with morphological and chemical analysis. They accepted 24 species in Dirina, 9 of which were described as new to science.