| Pseudoparmelia | |
|---|---|
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| Pseudoparmelia uleana | |
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Fungi |
| Division: | Ascomycota |
| Class: | Lecanoromycetes |
| Order: | Lecanorales |
| Family: | Parmeliaceae |
| Genus: | Pseudoparmelia Lynge (1914) |
| Type species | |
| Pseudoparmelia cyphellata Lynge (1914) | |
Pseudoparmelia is a genus of lichen-forming fungi in the family Parmeliaceae. The genus has a pantropical distribution.
It was circumscribed by Bernt Arne Lynge in 1914, who distinguished the genus from Parmelia by the presence of pseudocyphellae on the underside of the lichen thallus. [1] However, this distinguishing characteristic was later shown to be an artifact caused by torn rhizines. [2]
The genus was not widely accepted until it was redefined by Mason Hale in the 1970s to include parmelioid lichens with a pored epicortex and narrow, non-ciliate lobes. Further research revealed that this broader definition included a heterogeneous group of species, leading to a more restricted circumscription with most species being transferred to other genera. [2]
Molecular phylogenetic studies have shown that Pseudoparmelia forms a distinct lineage within the Parmeliaceae, closely related to the genera Relicina and Relicinopsis. These three genera share features including a pored epicortex, isolichenan as cell wall polysaccharide, and relatively small ascospores. The genus has its centres of distribution in the Neotropics and southern Africa. [2]
The main body (thallus) of Pseudoparmelia has a yellowish tint in both its outer layer (upper cortex ) and inner tissue (medulla), caused by the presence of chemicals called secalonic acids. The upper surface has microscopic pores in its protective outer layer, known as a pored epicortex . The lobes of the thallus are narrow and lack hair-like projections called cilia . [2]
On the thallus underside, Pseudoparmelia species have a pale surface with simple root-like structures (rhizines) that attach the lichen to its substrate . The fungal component of these lichens contains isolichenan in its cell walls, a type of polysaccharide that helps give the lichen structure. The cortex contains small amounts of the compound atranorin, while the medulla contains β-orcinol depsidones. [2]
When reproducing, these lichens produce small, ellipsoid to nearly spherical ascospores . They also produce another type of reproductive cell called conidia, which are elongated and can be either bifusiform (tapering at both ends) or thread-like in shape. [2]
Pseudoparmelia species are found primarily in two regions of the world: tropical and subtropical America (the Neotropics) and southern Africa. They can be distinguished from similar-looking genera by their unique combination of chemical compounds, particularly the presence of secalonic acids and absence of usnic acid, as well as their lack of specialised structures like bulbate cilia that are found in related genera. A unique chemical feature of the genus is the presence of terphenyl derivatives called butlerins, compounds that are uncommon in lichen-forming fungi but more frequently found in non-lichenised mushrooms and other basidiomycetes. [2]
Parmelia is a genus of medium to large foliose (leafy) lichens. It has a global distribution, extending from the Arctic to the Antarctic continent but concentrated in temperate regions. There are about 40 species in Parmelia. In recent decades, the once large genus Parmelia has been divided into a number of smaller genera according to thallus morphology and phylogenetic relatedness.
The Parmeliaceae is a large and diverse family of Lecanoromycetes. With over 2700 species in 71 genera, it is the largest family of lichen-forming fungi. The most speciose genera in the family are the well-known groups: Xanthoparmelia, Usnea, Parmotrema, and Hypotrachyna.
Myelochroa is a genus of foliose lichens in the family Parmeliaceae. They are commonly known as axil-bristle lichens. It was created in 1987 to contain species formerly placed in genus Parmelina that had a yellow-orange medulla due to the presence of secalonic acids. Characteristics of the genus include tightly attached thalli with narrow lobes, cilia on the axils, and a rhizinate black lower surface. Chemical characteristics are the production of zeorin and related triterpenoids in the medulla. Myelochroa contains about 30 species, most of which grow on bark. The genus has centres of distribution in Asia and North America.
Melanohalea is a genus of foliose lichens in the family Parmeliaceae. It contains 30 mostly Northern Hemisphere species that grow on bark or on wood. The genus is characterised by the presence of pseudocyphellae, usually on warts or on the tips of isidia, a non-pored epicortex and a medulla containing depsidones or lacking secondary metabolites. Melanohalea was circumscribed in 2004 as a segregate of the morphologically similar genus Melanelia, which was created in 1978 for certain brown Parmelia species. The methods used to estimate the evolutionary history of Melanohalea suggest that its diversification primarily occurred during the Miocene and Pliocene epochs.
Melanelixia is a genus of foliose lichens in the family Parmeliaceae. It contains 15 Northern Hemisphere species that grow on bark or on wood. The genus is characterized by a pored or fenestrate epicortex, and the production of lecanoric acid as the primary chemical constituent of the medulla. Melanelixia was circumscribed in 2004 as a segregate of the related genus Melanelia.
Flavoparmelia is a genus of foliose lichens in the family Parmeliaceae. Because of their appearance, they are commonly known as greenshield lichens. The widely distributed genus contains 32 species. It was circumscribed by American lichenologist Mason Hale in 1986 to contain 17 former Pseudoparmelia species with broad lobes, usnic acid in the cortex, and isolichenan in the cell walls.
Canoparmelia is a genus of lichen-forming fungi in the family Parmeliaceae. The widespread genus contains about 35 species. Canoparmelia, a segregate of the parmelioid lichen genus Pseudoparmelia, was circumscribed by John Elix and Mason Hale in 1986.
Punctelia is a genus of foliose lichens belonging to the large family Parmeliaceae. The genus, which contains about 50 species, was segregated from genus Parmelia in 1982. Characteristics that define Punctelia include the presence of hook-like to thread-like conidia, simple rhizines, and point-like pseudocyphellae. It is this last feature that is alluded to in the vernacular names speckled shield lichens or speckleback lichens.
Relicina is a genus of foliose lichens belonging to the large family Parmeliaceae. It contains 59 species.
Xanthoparmelia is a genus of foliose lichens in the family Parmeliaceae. This genus of lichen is commonly found in the United States, South America, southern Africa, Europe, Australia, and New Zealand.
Everniopsis is a fungal genus in the family Parmeliaceae. It consists of a single species, the bark-dwelling lichen Everniopsis trulla, which occurs in Africa and South America.
Psiloparmelia is a genus of lichen belonging to the family Parmeliaceae. It contains 13 Southern Hemisphere species, most of which are found growing on rocks at high elevations in South America. There are several characteristic features of the genus that are used to distinguish it from the morphologically similar genera, such as Arctoparmelia, Flavoparmelia, and Xanthoparmelia. These include a dark, velvety lower thallus surface that usually lacks rhizines, a negative test for lichenan, and a high concentration of usnic acid and atranorin in the cortex.
Parmotrema adspersum is a species of lichen in the family Parmeliaceae. It was originally described as a species of Parmelia by Edvard August Vainio in 1907. John Elix transferred it to Parmotrema in 2002, reasoning that its thick-walled ascospores are typical of that genus. Parmotrema adspersum is common in Thailand and the Philippines.
Parmotrema rampoddense, commonly known as the long-whiskered ruffle lichen, is a species of foliose lichen in the family Parmeliaceae. It is widely distributed in tropical regions and grows on the bark of oak and palm trees.
Xanthoparmelia lineola, commonly known as the tight rock-shield, is a foliose lichen species in the genus Xanthoparmelia. It is a common species with a temperate distribution. Found in North America and South Africa, it grows on rocks.
Bulbothrix meizospora is a species of foliose lichen in the family Parmeliaceae. It is found in Africa, Asia, and South America, where it grows on tree bark.
Punctelia punctilla is a species of foliose lichen in the family Parmeliaceae. It is found in Africa, South America, and North America, where it grows on bark and on rocks. The main characteristics that distinguish Punctelia punctilla from other species of Punctelia are the presence of isidia on the thallus surface, a pale brown thallus undersurface, and the presence of lecanoric acid in the medulla.
Punctelia graminicola is a species of foliose (leafy) lichen in the family Parmeliaceae. It grows on rocks, and, less frequently, on bark in North America, South America, and East Africa. It has a blue-grey thallus measuring up to about 15 cm (6 in), covered with tiny pores called pseudocyphellae. Sometimes the lichen forms small lobes that project out from the surface. Fruiting bodies are uncommon in this species; if present, they resemble small cups with a brown internal disc measuring 3–10 mm (0.1–0.4 in) in diameter. A lookalike species, Punctelia hypoleucites, is not readily distinguishable from Punctelia graminicola by appearance or habitat alone; these species can only be reliably differentiated by examining the length of their conidia.
Usnocetraria is a small genus of lichen-forming fungi in the family Parmeliaceae. It contains two species of corticolous (bark-dwelling), foliose lichens.
Pseudoparmelia kalbiana is a species of foliose lichen in the family Parmeliaceae. It is found in South America.
| Authority control databases: National |
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