The Arthoniaceae are a family of lichenized fungi in the order Arthoniales.[1] Species have a widespread distribution, but are especially prevalent in tropical areas. Collectively, the family has a highly variable ecology, some species lichenized with green algae, and others lichenicolous—growing on other lichens. Species can grow on leaves, bark and rock.[2] The genus was first described by Heinrich Gottlieb Ludwig Reichenbach in 1841.