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 Roccellaceae are a family of fungi in the order Arthoniomycetes. Most taxa are lichenized with green algae, although some are lichenicolous, growing on other lichens.
Enterographa is a genus of lichens in the family Roccellaceae.
Dirina is a genus of lichen-forming fungi in the family Roccellaceae. All Dirina species are crustose lichens with a whitish to greyish brown thallus, and live either on rock or on bark–some species can live on both. The photobiont partner is a member of the green algal genus Trentepohlia. Most species occur in the Northern Hemisphere, and are generally restricted to coastal habitats, where they may be locally quite common. Erythrin and lecanoric acid are lichen products that usually occur in Dirina species, along with several other unidentified substances.
Roccella is a genus of 23 species of lichens in the family Roccellaceae. The genus was circumscribed by Swiss botanist Augustin Pyramus de Candolle in 1805, with Roccella fuciformis as the type species.
Crocellina is a monotypic fungal genus in the family Roccellaceae. It contains the single species Crocellina cinerea, a saxicolous (rock-dwelling), crustose lichen that is endemic to Socotra Island in the Indian Ocean. This species was first described in 1882 by Swiss botanist Johannes Müller Argoviensis as Dirina cinerea, and later transferred to genus Roccellina in 1983. Crocellina was circumscribed in 2014 by Anders Tehler and Damien Ernst, following molecular phylogenetic analysis and revision of the Roccellaceae.
Vigneronia is a genus of lichen-forming fungi in the family Roccellaceae. It has five species. The genus was circumscribed in 2014 by Damien Ernst, with Vigneronia spieri assigned as the type species. This species, originally described as Schismatomma spieri from collections made in the Galápagos Islands, has since been recorded from mainland Ecuador and the Antilles (Curaçao). The genus is named after Ernst's wife, Nathalie Vigneron, who accompanied him on collecting trips.
Psoronactis is a monotypic fungal genus in the family Roccellaceae. It contains the single species Psoronactis dilleniana, a saxicolous (rock-dwelling), crustose lichen. This species was first described in 1799 by Swedish lichenologist Erik Acharius as Lichen dillenianus. The taxon was shuffled to several genera in the 1800s as different authors had different opinions on how to classify the species; in more modern times, it was transferred to genus Lecanographa in 2013. Psoronactis was circumscribed in 2014 by Damien Ernst and Anders Tehler, following molecular phylogenetic analysis and revision of the Roccellaceae that showed the species occupied a distinct lineage in the family. The genus name alludes to the lichen products present in its thallus: psoromic acid and 2'-O-demethylpsoromic acid. It is these compounds that differentiate it chemically from the similar genus Lecanactis.
Gyrographa is a genus of lichen-forming fungi in the family Roccellaceae. The genus was circumscribed in 2014 by Damien Ernst and Anders Tehler, with Gyrographa gyrocarpa assigned as the type species. This lichen, originally described by Julius von Flotow in 1825, was first placed in the genus Opegrapha. Species in the genus have a crustose thallus lacking a cortex, and a dark brown prothallus. The photobiont partner is trentepholioid. The hypothecium is thick and carbonised, and the ascospores lack a gelatinous sheath; these characteristics distinguish it from Opegrapha species. The genus name alludes to the gyrose ascomata of the type species.
Diromma is a monotypic fungal genus in the family Roccellaceae. It contains the single species Diromma dirinellum, a rare crustose lichen that grows as a parasite on the lichen Dirina ceratoniae. It has a distribution restricted to the Mediterranean Basin.
Gyronactis is a genus of lichen-forming fungi in the family Roccellaceae. It has two species. The genus was circumscribed by Damien Ernst and Anders Tehler in 2014, with G. asiatica assigned as the type species. This lichen, formerly placed in Lecanactis, is only known from the type locality in Myanmar. The genus name alludes to both its similarity with Lecanactis and the presence of gyrophoric acid in the thallus.
Pseudoschismatomma is a monotypic fungal genus in the family Roccellaceae. It contains the single species Pseudoschismatomma rufescens, a corticolous (bark-dwelling), crustose lichen. This species was first described in 1794 by Christiaan Hendrik Persoon as Opegrapha rufescens. Pseudoschismatomma was circumscribed in 2014 by Damien Ernst and Anders Tehler, following molecular phylogenetic analysis and revision of the Roccellaceae. The genus name alludes to its similarity with genus Schismatomma, particularly S. graphidioides. It differs from this species in having a distinct brown true exciple.
Ocellomma is a genus of lichen-forming fungi in the family Roccellaceae. The genus was circumscribed in 2014 by Damien Ertz and Anders Tehler, following a molecular phylogenetic-based revision of the Roccellaceae. The type species, O. picconianum, was originally named Lecania picconiana by Francesco Baglietto in 1862, described from specimens collected in Italy. DNA-based phylogenetic analysis showed that it occupied a distinct genetic lineage, deserving of recognition as a new genus. The genus name Ocellomma alludes to the whitish rims on the small ascomata that contrast with the discs, giving them the appearance of small eyes.
Dirina catalinariae is a species of saxicolous (rock-dwelling), crustose lichen in the family Roccellaceae. It occurs in the southwestern United States, Mexico, and the Galápagos Islands.
Dirina angolana is a species of corticolous (bark-dwelling), crustose lichen in the family Roccellaceae. Found in Angola, it was formally described as a new species in 2013 by lichenologists Anders Tehler and Damien Ertz. The type specimen was collected by the first author north of Palmeirinhas. It is only known to occur in Angola, where it grows preferentially on baobab tree trunks, usually near the sea. The species epithet refers to the country of its type locality.
Dirina astridae is a species of saxicolous (rock-dwelling), crustose lichen in the family Roccellaceae. Found in Mauritius, it was formally described as a new species in 2013 by Anders Tehler. The type specimen was collected by the author from the peak of Signal Mountain in Port Louis. The species epithet astridae refers to Tehler's daughter Astrid, "who led the way to this species on a joint field trip to Mauritius".
Dirina badia is a species of crustose lichen in the family Roccellaceae. It is found on the small desert mountains of northern Peru, where it grows on both stone and on bark.
Dirina candida is a species of saxicolous (rock-dwelling), crustose lichen in the family Roccellaceae. It is found in the southern Mediterranean Basin, with a range extending east to Egypt and Libya. It grows on calcareous rocks that are close to the sea. The lichen was formally described as a new species in 1885 by Johannes Müller Argoviensis from specimens collected in Alexandria, Egypt. Anders Teher and Damien Ertz transferred it to Dirina in 2013. Tehler had previously (1983) referred this species to Dirina immersa, but later molecular phylogenetic analysis revealed that it should instead be considered a distinct species, despite the two sharing the same appearance, morphology, and chemistry.
Dirina pacifica is a species of saxicolous (rock-dwelling), crustose lichen in the family Roccellaceae. It is found in both Hawaii and the Galápagos Islands, where it grows in coastal outcrops. The lichen was formally described as a new species in 2013 by Anders Tehler and Damien Ertz. The type specimen was collected from Koolaupoko. The species epithet refers to the Pacific Ocean. It has a creamy white to greyish or brownish thallus lacking pruina, and a chalk-like medulla. Its ascomata have a circular outline up to 1.5 mm in diameter, with a whitish-grey disc. Its ascospores measure 19–27 by 4–5 μm. Dirina pacifica contains the lichen products erythrin, lecanoric acid, and sometimes three unidentified substances named "C", "F", and "G".
Fulvophyton is a genus of lichen-forming fungi in the family Roccellographaceae. It has 11 species. Fulvophyton is characterised by its crust-like thallus, which is often pale yellowish-brown in colour. This genus features a photobiont from the green algal genus Trentepohlia and exhibits a unique arrangement of reproductive structures.
