The Arthoniales is the second largest order of mainly crustose lichens, but fruticose lichens are present as well. The order contains around 1500 species, while the largest order with lichenized fungi, the Lecanorales, contains more than 14000 species.
The Baeomycetales are an order of mostly lichen-forming fungi in the subclass Ostropomycetidae, in the class Lecanoromycetes. It contains 8 families, 33 genera and about 170 species. As a result of molecular phylogenetics research published in the late 2010s, several orders were folded into the Baeomycetales, resulting in a substantial increase in the number of taxa.
The Coccotremataceae are a family of lichen-forming fungi in the order Pertusariales. Species in this widely distributed family grow on bark or rocks, especially in maritime regions.
Trapelia is a genus of lichenized fungi in the family Trapeliaceae.
Rimularia is a genus of lichenized fungi in the family Trapeliaceae. Rimularia was circumscribed by Finnish botanist William Nylander in 1868.
Cladia is a genus of lichen-forming fungi in the family Cladoniaceae. Cladia species have a crustose or squamulose (scaly) primary thallus and a fruticose, secondary thallus, often referred to as pseudopodetium. The type species of the genus, Cladia aggregata, is widely distributed, occurring in South America, South Africa, Australasia and South-East Asia to southern Japan and India. Most of the other species are found in the Southern Hemisphere.
Kantvilasia is a lichen genus in the family Pilocarpaceae. This is a monotypic genus, containing the single species Kantvilasia hians.
Amandinea is a genus of lichenized fungi in the family Caliciaceae. Genetic studies indicates that the genus Amandinea and Buellia are the same, although this is not widely accepted.
Bactrospora is a genus of lichen-forming fungi of uncertain familial placement in the order Arthoniales. It was circumscribed by Abramo Bartolommeo Massalongo in 1852.
Thelidium is a genus of lichen-forming fungi in the family Verrucariaceae. The genus was circumscribed in 1855 by Italian lichenologist Abramo Bartolommeo Massalongo, who assigned Thelidium amylaceum as the type species.
Collemopsidium is a genus of fungi in the family Xanthopyreniaceae. Some members of this genus are marine species, and described as "borderline lichens" or "algicolous" fungi. The genus was circumscribed by Finnish botanist William Nylander in 1881.
Steinia is a genus of lichen-forming fungi in the family Aphanopsidaceae. It has three species.
Fuscidea is a genus of crustose lichens in the family Fuscideaceae. It has about 40 species. The genus was circumscribed in 1972 by lichenologists Volkmar Wirth and Antonín Vězda, with Fuscidea aggregatilis assigned as the type species.
Chrysothrix is a genus of lichen-forming fungi in the family Chrysothricaceae. They are commonly called gold dust lichens or sulfur dust lichens, because they are bright yellow to greenish-yellow, sometimes flecked with orange, and composed entirely of powdery soredia. Apothecia are never present in North American specimens.
Austropeltum is a genus of lichenized fungi in the family Sphaerophoraceae. The genus is monotypic, containing the single species Austropeltum glareosum, found in Australia and New Zealand.
Mycoblastus is a genus of crustose lichens in the family Tephromelataceae. Members of the genus are commonly called blood lichens.
Endohyalina is a genus of 10 species of corticolous lichens in the family Caliciaceae. The genus was circumscribed by Bernhard Marbach in 2000, with Endohyalina rappii designated as the type species.
Roccellinastrum is a genus of lichen-forming fungi in the family Pilocarpaceae. It has seven species.
Megalospora is a genus of lichen-forming fungi in the family Megalosporaceae.
