Arthrorhaphis is a genus of lichen-forming fungi in the monotypic family Arthrorhaphidaceae. It has 13 species.[2] The genus was circumscribed by Theodor Magnus Fries in 1860. The family was proposed by lichenologists Josef Poelt and Josef Hafellner in 1976.[3] Species in this family have a widespread distribution in temperate and montane habitats. They grow symbiotically with green algae, or parasitically on other lichens.[4] The family Arthrorhaphidaceae has an uncertain taxonomic placement in the class Lecanoromycetes; that is, it is incertae sedis with respect to ordinal placement.[2]