Roccellaceae

The Roccellaceae are a family of mostly lichen-forming fungi in the order Arthoniales, established by the French botanist François Fulgis Chevallier in 1826. Species in the family exhibit various growth forms, including crustose and fruticose (shrub-like) thalli, and diverse reproductive structures. Roccellaceae species typically have disc-like () or slit-like () fruiting bodies, often with distinct blackened () margins. Molecular phylogenetics studies have revealed considerable genetic diversity and complex evolutionary histories within the family.

Convergent evolution in the Roccellaceae has led to multiple independent developments of similar traits, particularly in growth forms. Molecular studies have divided the family into two main phylogenetic groups, each characterised by distinct internal structures. These findings have prompted major taxonomic revisions, clarifying their evolutionary relationships. Roccellaceae produce lichen substances from different chemical classes, some of which have been historically important as sources of purple or red dyes like orchil.