Xanthoparmelia

Last updated

Contents

Xanthoparmelia
Xanthoparmelia conspersa - Flickr - pellaea (1).jpg
Xanthoparmelia conspersa
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Fungi
Division: Ascomycota
Class: Lecanoromycetes
Order: Lecanorales
Family: Parmeliaceae
Genus: Xanthoparmelia
(Vain.) Hale (1974)
Type species
Xanthoparmelia conspersa
(Ehrh. ex Ach.) Hale (1974)
Synonyms [1]
List
  • Parmelia sect. XanthoparmeliaVain. (1890)
  • AlmborniaEssl. (1981)
  • Chondropsis Nyl. (1869)
  • ChondropsisNyl. ex Cromb. (1879)
  • KaroowiaHale (1989)
  • NamakwaHale (1988)
  • NeofusceliaEssl. (1978)
  • OmphalodiellaHenssen (1991)
  • Parmelia sect. XanthoparmeliaVain. (1890)
  • Paraparmelia Elix & J.Johnst. (1986)
  • Placoparmelia Henssen (1992)
  • XanthomaculinaHale (1985)

Xanthoparmelia (commonly known as green rock shields or rock-shield lichens) is a genus of foliose lichens in the family Parmeliaceae. [2] [3] : 134  This genus of lichen is commonly found in the United States, as well as Australia, New Zealand and Ecuador.

The name means 'golden yellow parmelia'. The photobiont (photosynthetic partner) is Trebouxia (a genus of green algae).

Taxonomy

Xanthoparmelia was originally conceived of as a section of the genus Parmelia by Brazilian lichenologist Edvard August Vainio in 1890, to accommodate yellow species with narrow lobes. [4] Mason Hale considered that the combination of traits including the presence of the cortical pigment usnic acid, and the microscopic structure of the upper cortex were sufficient criteria to segregate Xanthoparmelia from the genus Parmelia. He formally transferred 93 species, including the type, Xanthoparmelia conspersa . [5]

In a 2004 study, molecular analysis was used to help revise the classification of parmelioid lichens containing Xanthoparmelia-type lichenan. This analysis demonstrated that several genera previously segregated from Xanthoparmelia on the basis of physical characteristics did not form distinct clades within Xanthoparmelia, and so Neofuscelia, Chondropsis and Paraparmelia were synonymized with Xanthoparmelia. As a result of this work, 10 new species were published, and 129 new combinations into Xanthoparmelia were proposed. [6] Similarly, three south African genera, Almbornia, Namakwa, and Xanthomaculina, were synonymized with Xanthoparmelia after the limits of the genus were further explored and refined with molecular phylogenetics. [7] Karoowia, a genus that was characterized by features such as its subcrustose growth form and its presence of an arachiform vacuolar body in the ascospores, was synonymised with Xanthoparmelia when it was shown that its species cluster in different clades nested within Xanthoparmelia. [8] The genus Omphalodiella, proposed by Aino Henssen in 1991 to contain the Patagonian species Omphalodiella patagonica, [9] has since been shown to lie within Xanthoparmelia. [10]

Description

Xanthoparmelia consists of lichens that has a thallus ranging from leaf-like (foliose) to almost crust-like (subcrustose) and occasionally almost shrub-like (subfruticose), typically forming large, flat patches that are either loosely or tightly attached to the substrate . The thallus is composed of lobes which may vary from irregular to linear shapes, are often flat or can be twisted or folded (strongly convoluted), and lack hair-like projections ( cilia ) at the edges, which may be notched or lobed. [11]

The upper surface of the thallus is commonly pale yellow to yellow-green or grey-green, indicative of the presence of usnic acid, a substance common in lichens, or it may be a shade of brown if the lichen lacks usnic acid. This surface often develops irregular cracks and may or may not display patches of soredia (asexual reproductive structures that break away to form new lichens) or isidia (outgrowths that can also lead to new lichens). Lichens in this genus do not have pseudocyphellae, which are small pores on the surface. The upper cortex —the outer layer of the lichen—is composed of vertically aligned hyphae (the filamentous cells of fungi) or tightly packed cells with a pored outer layer ( epicortex ). These cells contain a specific type of lichen-specific polysaccharide known as Xanthoparmelia-type lichenan. The medulla, or internal layer beneath the cortex, is loosely structured and typically white, although it can be pigmented. The lower surface of the thallus can range from pale ivory to various shades of yellow, tan, brown, or black, and is covered to varying extents with rhizines (root-like structures) that typically do not branch. [11]

The reproductive structures of Xanthoparmelia include ascomata, known as apothecia, which are typically found on the surface of the thallus and may be slightly raised or stalked. The discs of these structures are initially concave but become flatter and distorted with age and are coloured from red-brown to brown or black. The ascospores produced in these structures are small, ellipsoidal, and each contains an arachiform vacuolar body, with eight spores per ascus. Another reproductive feature, conidiomata (pycnidia), are usually found immersed in the thallus and produce spores that are typically two-ended ( bifusiform ) or cylindrical. [11]

Chemically, the cortex of Xanthoparmelia lichens contains either usnic acid or an unknown brown pigment, while the medulla may contain a variety of chemical compounds including orcinol depsides, orcinol depsidones, β-orcinol depsides, β-orcinol depsidones, anthraquinones, aliphatic acids, and amino acid derivatives. [11]

Species

Xanthoparmelia is the largest genus of lichen-forming fungi, with more than 800 accepted species. [12] Species include:

Related Research Articles

<i>Parmelia</i> (fungus) Genus of lichens

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.

<span class="mw-page-title-main">Parmeliaceae</span> Family of lichens

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.

<i>Myelochroa</i> Genus of lichens

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.

<i>Melanohalea</i> Genus of lichen

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.

<i>Flavoparmelia</i> Genus of fungi

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.

<i>Parmotrema</i> Genus of fungi

Parmotrema is a genus of lichen belonging to the family Parmeliaceae. It is a large genus, containing an estimated 300 species, with a centre of diversity in subtropical regions of South America and the Pacific Islands.

<i>Punctelia</i> Genus of foliose lichens

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.

<i>Relicina</i> Genus of lichens

Relicina is a genus of foliose lichens belonging to the large family Parmeliaceae. It contains 59 species.

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.

<i>Xanthoparmelia conspersa</i> Species of foliose lichen in the family Parmeliaceae

Xanthoparmelia conspersa, commonly known as the peppered rock-shield, is a foliose lichen and the type species of genus Xanthoparmelia. It is widely distributed in temperate zones, and has been recorded from Japan, Europe, Africa, North America, and South America.

Parmotrema albinatum is a species of foliose lichen in the family Parmeliaceae that is found in Hawaii. It was originally described in 2001 as Rimelia albinata. Later phylogenetic analysis demonstrated that the genus Rimelia was synonymous with Parmotrema, so this species was transferred to that genus. The lichen is characterized by the sorediate and short-lacinulate thallus with salazinic acid in the medulla and traces of lobaric acid. The upper surface of the thallus is whitish, which probably a result of the thickness of the thick upper cortex.

<i>Crespoa</i> Genus of fungi

Crespoa is a genus of five species of lichen in the family Parmeliaceae. Species in this genus are characterized by having an upper thallus surface that is wrinkled and reticulately ridged to coarsely foveolate.

Remototrachyna is a genus of foliose lichens in the large family Parmeliaceae. It was separated from the genus Hypotrachyna based on the structure of the excipulum and genetic differences.

Austroparmelina is a genus of foliose lichens in the large family Parmeliaceae. It contains species formerly placed in the genera Parmelina and Canoparmelia. All species of Austroparmelina have an Australasian-South African distribution.

Emodomelanelia is a lichen genus in the family Parmeliaceae. It is monotypic, containing the single foliose Himalayan species Emodomelanelia masonii.

<i>Notoparmelia</i> Genus of lichens

Notoparmelia is a genus of foliose lichens in the family Parmeliaceae. It includes 18 species that grow on bark and rocks, and are mostly distributed in the Southern Hemisphere. The genus was created in 2014 as a segregate of Parmelia.

Parmelia mayi is a species of foliose lichen in the family Parmeliaceae. It is found in the northern Appalachian Mountains of eastern North America, where it grows on rocks and on the trunks of paper birch and balsam fir. Parmelia mayi is morphologically indistinguishable from Parmelia saxatilis, but is distinct in its distribution, chemistry, and genetics.

<i>Parmelia fraudans</i> Species of lichen

Parmelia fraudans is a species of foliose lichen in the family Parmeliaceae. It is found in Europe and North America, where it grows on rocks.

Xanthoparmelia salazinica is a species of lichen in the family Parmeliaceae. Found in South Africa, it was described as a new species in 1989 by American lichenologist Mason Hale. He classified it in Karoowia, a genus that has since been placed in synonymy with Xanthoparmelia following molecular phylogenetic analysis published in 2010.

Xanthoparmelia isidiovagans is a species of foliose lichen in the family Parmeliaceae

References

  1. ↑ "Synonymy: Xanthoparmelia (Vain.) Hale, Phytologia 28(5): 485 (1974)". Species Fungorum . Retrieved 26 November 2021.
  2. ↑ Smith HB, Dal Grande F, Muggia L, Keuler R, Divakar PK, Grewe F, Schmitt I, Lumbsch HT, Leavitt SD (2020). "Metagenomic data reveal diverse fungal and algal communities associated with the lichen symbiosis". Symbiosis. 82 (1–2): 133–147. doi: 10.1007/s13199-020-00699-4 . hdl: 11577/3440801 .
  3. ↑ Field Guide to California Lichens, Stephen Sharnoff, Yale University Press, 2014, ISBN   978-0-300-19500-2
  4. ↑ Vainio, E. (1890). Lichens of Brazil. Acta Societatis pro Fauna et Flora Fennica (in Latin). Vol. 7. Helsinki: Heredum J. Simelii. p. 60.
  5. ↑ Hale, Mason E. (1974). "Bulbothrix, Parmelina, Relicina, Xanthoparmelia, four new genera in the Parmeliaceae (Lichenes)". Phytologia. 28 (5): 479–490.
  6. ↑ Blanco, Oscar; Crespo, Ana; Elix, John A.; Hawksworth, David L.; Lumbsch, H. Thorsten (2004). "A molecular phylogeny and a new classification of parmelioid lichens containing Xanthoparmelia-type lichenan (Ascomycota: Lecanorales)". Taxon. 53 (4): 959–975. doi:10.2307/4135563. JSTOR   4135563.
  7. ↑ Thell, Arne; Tassilo, Feuerer; Elix, John A.; Kärnefelt, Ingvar (2006). "A contribution to the phylogeny and taxonomy of Xanthoparmelia (Ascomycota, Parmeliaceae)". Journal of the Hattori Botanical Laboratory. 100: 797–807. doi:10.18968/jhbl.100.0_797.
  8. ↑ Amo de Paz, Guillermo; Lumbsch, H. Thorsten; Cubas, Paloma; Elix, John A.; Crespo, Ana (2010). "The genus Karoowia (Parmeliaceae, Ascomycota) includes unrelated clades nested within Xanthoparmelia". Australian Systematic Botany. 23 (3): 173. doi:10.1071/SB09055.
  9. ↑ Henssen, Aino (1991). "Omphalodiella patagonica, a new peltate lichen genus and species from South America". The Lichenologist. 23 (4): 333–342. doi:10.1017/s002428299100049x.
  10. ↑ de Paz, Guillermo Amo; Lumbsch, H. Thorsten; Cubas, Paloma; Elix, John A.; Crespo, Ana (2010). "The morphologically deviating genera Omphalodiella and Placoparmelia belong to Xanthoparmelia (Parmeliaceae)". The Bryologist. 113 (2): 376–386. doi:10.1639/0007-2745-113.2.376.
  11. 1 2 3 4 Cannon, P.; Divakar, P.; Yahr, R.; Aptroot, A.; Clerc, P.; Coppins, B.; Fryday, A.; Sanderson, N.; Simkin, J. (2023). Lecanorales: Parmeliaceae, including the genera Alectoria, Allantoparmelia, Arctoparmelia, Brodoa, Bryoria, Cetraria, Cetrariella, Cetrelia, Cornicularia, Evernia, Flavocetraria, Flavoparmelia, Hypogymnia, Hypotrachyna, Imshaugia, Melanelia, Melanelixia, Melanohalea, Menegazzia, Montanelia, Nesolechia, Parmelia, Parmelina, Parmeliopsis, Parmotrema, Platismatia, Pleurosticta, Protoparmelia, Pseudephebe, Pseudevernia, Punctelia, Raesaenenia, Tuckermannopsis, Usnea, Vulpicida and Xanthoparmelia (PDF). Revisions of British and Irish Lichens. Vol. 33. p. 82.
  12. ↑ Leavitt, Steven D.; Kirika, Paul M.; Amo De Paz, Guillermo; Huang, Jen-Pan; Hur, Jae-Seoun; Elix, John A.; Grewe, Felix; Divakar, Pradeep K.; Lumbsch, H. Thorsten (2018). "Assessing phylogeny and historical biogeography of the largest genus of lichen-forming fungi, Xanthoparmelia (Parmeliaceae, Ascomycota)". The Lichenologist. 50 (3): 299–312. doi:10.1017/S0024282918000233.
  13. ↑ Dobson, Frank S. (2005). Lichens An Illustrated Guide to the British and Irish Species. The Richmond Publishing Co.Ltd. pp. 459–460. ISBN   978-0-85546-095-2.
  14. ↑ Hale Jr, M.E. 1984. New species of Xanthoparmelia (Vain.) Hale (Ascomycotina: Parmeliaceae). Mycotaxon. 20(1):73-79
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.