Athallia is a genus of lichen-forming fungi in the family Teloschistaceae. Most species have a poorly developed or almost invisible thallus, with the fruiting bodies often appearing to sit directly on the substrate. The genus occurs on bark, wood, and rock, and is found mainly in temperate regions of the Northern Hemisphere. All species share a characteristic set of orange anthraquinone pigments known as chemosyndrome A.

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