A lichen is a hybrid colony of algae or cyanobacteria living symbiotically among filaments of multiple fungi species, along with a yeast embedded in the cortex or "skin", in a mutualistic relationship.
Peltigerales is an order of lichen-forming fungi belonging to the class Lecanoromycetes in the division Ascomycota. The taxonomy of the group has seen numerous changes; it was formerly often treated as a suborder of the order Lecanorales. It contains two suborders, eight families and about 45 genera such as Lobaria and Peltigera.
The Pannariaceae are a family of lichens in the order Peltigerales. Species from this family have a widespread distribution, but are especially prevalent in southern temperate regions.
Spilonema is a genus of lichen-forming fungi in the family Coccocarpiaceae. The genus was circumscribed by Jean-Baptiste Édouard Bornet in 1856.
A fruticose lichen is a form of lichen fungi that is characterized by a coral-like shrubby or bushy growth structure. It is formed from a symbiotic relationship of a photobiont such as green algae or less commonly cyanobacteria and one, two or more mycobionts. Fruticose lichens are not a monophyletic and holophyletic lineage, but are a form encountered in many classes. Fruticose lichens have a complex vegetation structure, and are characterized by an ascending, bushy or pendulous appearance. As with other lichens, many fruticose lichens can endure high degrees of desiccation. They grow slowly and often occur in habitats such as on tree barks, on rock surfaces and on soils in the Arctic and mountain regions.
Symbiosis in lichens is the mutually beneficial symbiotic relationship of green algae and/or blue-green algae (cyanobacteria) living among filaments of a fungus, forming lichen.
Hydropunctaria is a genus of saxicolous (rock-dwelling), crustose lichens in the family Verrucariaceae. The genus includes both aquatic and amphibious species, with members that colonise either marine or freshwater habitats. The type species, Hydropunctaria maura, was formerly classified in the large genus Verrucaria. It is a widely distributed species common to littoral zones. Including the type species, five Hydropunctaria lichens are considered marine species: H. adriatica, H. amphibia, H. aractina, H. orae, and H. oceanica.
Toensbergia is a genus of lichen-forming fungi in the family Sporastatiaceae. The genus was circumscribed by Mika Bendiksby and Einar Timdal in 2013. The genus name honours Norwegian lichenologist Tor Tønsberg, "in appreciation of his important work on sorediate, corticolous lichens". The type species is Toensbergia leucococca, which was formerly classified in genus Hypocenomyce, presumably due to its resemblance to Hypocenomyce xanthococca.
Steineropsis is a genus of lichen-forming fungi in the family Pannariaceae. It has two species. The genus was circumscribed by Toby Spribille and Lucia Muggia in 2010, with Steineropsis alaskana assigned as the type species. The type specimen of this lichen was found in Skagway, Alaska, where it was growing on a rock in a snowbed at an altitude of 1,051 m (3,448 ft). The generic name alludes to a resemblance to the genus Steinera. A second species, Steineropsis laceratula, also found in Alaska, was added to the genus in 2020. Molecular phylogenetic analysis showed that Steineropsis has a sister taxon relationship to genus Protopannaria.
Atrophysma is a fungal genus in the family Pannariaceae. It contains the single species Atrophysma cyanomelanos, a crustose lichen found only in Alaska.
Massalongiaceae is a small family of lichen-forming fungi in the order Peltigerales. It has three genera and seven species.
The following outline provides an overview of and topical guide to lichens.
Koerberiaceae is a small family of lichen-forming fungi in the order Peltigerales. It contains 3 genera and 9 species. The family was proposed by Toby Spribille and Lucia Muggia in 2012, after molecular phylogenetic analysis revealed the existence of three lineages of lichen-forming fungi in the suborder Peltigerineae of the order Peltigerales. The lineages represented the genera Steinera, Koerberia, and Vestergrenopsis. The latter genus was later folded into synonymy with Tingiopsidium.
Botryolepraria is a genus of saxicolous (rock-dwelling), byssoid (cottony) lichens of uncertain familial placement in the order Verrucariales. It has two species. Both species grow in damp conditions, such as on cave walls, particularly in areas with minimal light.
Dendriscosticta is a genus of foliose lichens in the family Peltigeraceae. The genus was circumscribed in 2013 by lichenologists Bibiana Moncada and Robert Lücking with Dendriscosticta wrightii assigned as the type species. The genus, a segregate of Sticta, was created to contain species in the Sticta wrightii clade. Dendriscosticta has a sister taxon relationship with the genera Yoshimuriella and Lobariella. Dendriscosticta is distinguished from Sticta by the presence of algae in the excipulum.
Racoleus is a genus of two species of lichen-forming fungi of uncertain familial placement in the order Capnodiales. Both species of Racoleus are filamentous lichens with Trentepohlia as the photobiont partner. The lichens form thalli in the form of felt-like, blackish-brown cushions that grow under shaded conditions on siliceous rocks.
Normandina pulchella, commonly known as the elf-ear lichen or blue heart, is a species of squamulose lichen in the family Verrucariaceae. This cosmopolitan species is widely distributed across both hemispheres, where it thrives in moist microhabitats. It favours moss-covered deciduous trees and rocks, often colonising over mosses and bryophytes. It occasionally grows on bare bark and on other lichens. Distinctive features of N. pulchella include its bluish-green squamules (scales) with sharply raised margins, non-reactivity to standard chemical spot tests, and growth in humid habitats. Initially, Nannochloris normandinae, a green alga, was thought to be its photobiont. However, recent studies have revised this understanding, now suggesting Diplosphaera as the algal partner.
Myochroidea is a genus of lichen-forming fungi of uncertain familial placement in the order Lecanorales. It has four species of grey or brown-grey crustose lichens.
Puttea is a genus of lichen-forming fungi with uncertain familial placement in the order Lecanorales. The genus comprises four species. Finnish lichenologists Soili Stenroos and Seppo Huhtinen established the genus Puttea in 2009 for the lichen species formerly known as Lecidea margaritella, which has undergone various reclassifications. Molecular phylogenetics analyses have shown that Puttea margaritella does not align closely with genera like Fellhanera or Micarea, but its precise familial placement remains uncertain. Puttea is characterized by an indistinct, lichenized thallus composed of delicate fungal filaments and small algal cells. Its minute, round, whitish apothecia lack a distinct margin, and the asci, or spore-producing cells, are thick-walled, club-shaped, and contain eight spores, showing specific reactions with iodine-based stains. The type species of the genus, Puttea margaritella, typically inhabits boreal forests, growing on the liverwort species Ptilidium pulcherrimum and sometimes on decaying wood or bark. Initially thought to be confined to Europe, it has since been found in North America, particularly in Alaska and Québec, extending its known range. The species is parasitic, damaging its host, and is considered rare within its distribution.
Leptogidium is a genus of lichen-forming fungi in the family Pannariaceae. It has six species.
