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.
Porinaceae is a family of lichen-forming fungi in the order Gyalectales. While Trichotheliaceae was proposed as an alternative, Porinaceae is the widely accepted name following ongoing nomenclatural discussions. Most members of this family typically have a crust-like appearance and grow on a variety of surfaces, including tree bark, leaves, and rocks. Porinaceae is known for its diverse morphology, ranging from simple crust-like forms to more complex structures with distinct lobes or fan-shaped scales. Porinaceae species generate small, typically flask-shaped reproductive structures, which house spores essential for reproduction. It includes nine recognised genera and more than 365 species, with significant diversity in tropical and subtropical regions.
Verrucariaceae is a family of lichens and a few non-lichenised fungi in the order Verrucariales. The lichens have a wide variety of thallus forms, from crustose (crust-like) to foliose (bushy) and squamulose (scaly). Most of them grow on land, some in freshwater and a few in the sea. Many are free-living but there are some species that are parasites on other lichens, while one marine species always lives together with a leafy green alga.
Porina is a genus of crustose lichens in the family Porinaceae. As of August 2024, Species Fungorum accepts 161 species of Porina.
Gallaicolichen is a fungal genus that contains the single species Gallaicolichen pacificus, a foliicolous (leaf-dwelling) lichen. Originally discovered in Hawaii in 2007, G. pacificus has since been found in various locations across the Pacific, including Australia, New Caledonia, Vanuatu, the Philippines, and Japan. The lichen forms small, pale greenish-yellow to yellowish-grey patches on leaves, typically in mid-altitude forests and along forest edges. G. pacificus is notable for its unique reproductive structures called peltidiangia, which produce disc-shaped propagules (peltidia) for asexual reproduction. Initially, its taxonomic classification was uncertain, but recent discoveries of specimens with sexual reproductive structures have enabled scientists to confidently place it within the family Porinaceae.
Lepidostromatales is an order of fungi in the class Agaricomycetes. It is the only known order of basidiomycete fungi composed entirely of lichenized members. Morphologically, the fruiting bodies of all species are clavarioid. Six species are known, five of which were described within the span of 2007–2013. Due to its morphological similarity to the genus Multiclavula, its isolated phylogenetic position was not understood until quite recently. The photobionts that have been found in association with members of this group are not known to associate with any other types of lichenized fungi.
Crustose lichens are lichens that form a crust which strongly adheres to the substrate, making separation from the substrate impossible without destruction. The basic structure of crustose lichens consists of a cortex layer, an algal layer, and a medulla. The upper cortex layer is differentiated and is usually pigmented. The algal layer lies beneath the cortex. The medulla fastens the lichen to the substrate and is made up of fungal hyphae. The surface of crustose lichens is characterized by branching cracks that periodically close in response to climatic variations such as alternate wetting and drying regimes.
Lichens are symbiotic organisms made up of multiple species: a fungus, one or more photobionts and sometimes a yeast. They are regularly grouped by their external appearance – a characteristic known as their growth form. This form, which is based on the appearance of vegetative part of the lichen, varies depending on the species and the environmental conditions it faces. Those who study lichens (lichenologists) have described a dozen of these forms: areolate, byssoid, calicioid, cladoniform, crustose, filamentous, foliose, fruticose, gelatinous, leprose, placoidioid and squamulose. Traditionally, crustose (flat), foliose (leafy) and fruticose (shrubby) are considered to be the three main forms. In addition to these more formalised, traditional growth types, there are a handful of informal types named for their resemblance to the lichens of specific genera. These include alectorioid, catapyrenioid, cetrarioid, hypogymnioid, parmelioid and usneoid.
Lichen morphology describes the external appearance and structures of a lichen. These can vary considerably from species to species. Lichen growth forms are used to group lichens by "vegetative" thallus types, and forms of "non-vegetative" reproductive parts. Some lichen thalli have the aspect of leaves ; others cover the substrate like a crust, others such as the genus Ramalina adopt shrubby forms, and there are gelatinous lichens such as the genus Collema.
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.
Porina rivalis is a species of semi-aquatic, saxicolous (rock-dwelling), and crustose lichen in the family Porinaceae. Found in Great Britain, it was formally described as a new species in 2015 by lichenologist Alan Orange. The type specimen was collected in Nant Walch near Llanwrtyd Wells (Breconshire) at an altitude of 230 m (750 ft); here the lichen was found growing on stones submerged in a shaded stream. The species had been known previously from streams in Wales, but it had been incorrectly identified as Porina lectissima. Porina rivalis has also been recorded from streams in South-west England and North England. It has a thin brown thallus with prominent dark brown or black perithecia. Its ascospores are shaped like narrow ellipsoids, have three septa, and typically measure 13.0–17.5 by 4.0–5.5 μm.
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.
Porina mariae is a species of saxicolous (rock-dwelling) crustose lichen in the family Porinaceae. Found on Lord Howe Island, Australia, it was formally described as a new species in 1997 by lichenologist Patrick M. McCarthy. The type specimen was collected by the author on the track from Smoking Tree Ridge to Boat Harbour, where it was growing on deeply shaded basalt. The species epithet honours the author's wife, Marie Meaney-McCarthy, "in recognition of her unwavering encouragement and support".
Leproplaca cirrochroa is a widespread and common species of saxicolous (rock-dwelling), crustose lichen in the family Teloschistaceae. It grows up to 5 cm across, featuring a placodioid thallus with narrow, finger-like lobes that adhere closely to the surface, showing intricate division and ranging in colour from dirty orange to brownish orange, often with paler, pruinose orange ends.
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.
Sucioplaca is a single-species fungal genus in the family Teloschistaceae. It contains Sucioplaca diplacia, a saxicolous (rock-dwelling) crustose lichen. It is common and widely distributed in the Caribbean, Central America, and the Galápagos Islands, where it grows on coastal 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.
Porina boliviana is a species of foliicolous (leaf-dwelling) crustose lichen in the family Porinaceae. It was formally described as a new species in 2008 by the lichenologists Adam Flakus and Robert Lücking. They named it after the country where it was discovered, Bolivia. Flakus collected the type specimen from Nuevos Reyes village in the José Ballivián Province, where he found it growing on palm tree leaves in a lowland Amazon forest.
Callome is a fungal genus in the family Collemataceae. It consists of the single species Callome multipartita, a saxicolous (rock-dwelling), crustose lichen found in Northern Africa, Europe, and North America.
