''Xanthoparmelia'' (commonly known as green rock shields or rock-shield lichens) is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

foliose lichen Foliose lichen is one of the morphological classes of lichens, which are complex organisms that arise from the symbiotic relationship between fungi and a photosynthetic partner, typically algae. This partnership allows lichen to live in diverse ...

in the family

Parmeliaceae 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'' ( 822 ...

.Field Guide to California Lichens, Stephen Sharnoff, Yale University Press, 2014, ''Xanthoparmelia'' is synonymous with ''Almbornia'', ''Neofuscelia'', ''Chondropsis'', ''Namakwa'', ''Paraparmelia'', and ''Xanthomaculina''. 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 A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship.Trebouxia ''Trebouxia'' is a unicellular green alga.Silverside, A. J. (2009). Retrieved from http://www.bioref.lastdragon.org/Chlorophyta/''Trebouxia''.html It is a photosynthetic organism that can exist in almost all habitats found in polar, tropical, a ...

'' (a genus of

green algae The green algae (singular: green alga) are a group consisting of the Prasinodermophyta and its unnamed sister which contains the Chlorophyta and Charophyta/Streptophyta. The land plants (Embryophytes) have emerged deep in the Charophyte alga as ...

Identification

Distinguishing between species involves how much they are attached to the substrate, whether or not

isidia An isidium is a vegetative reproductive structure present in some lichens. Isidia are outgrowths of the thallus surface, and are corticated (i.e., containing the outermost layer of the thallus), usually with a columnar structure, and consisting ...

are present, lower surface color, and chemical

spot test Spot analysis, spot test analysis, or spot test is a chemical test, a simple and efficient technique where analytic assays are executed in only one, or a few drops, of a chemical solution, preferably in a great piece of filter paper, without using ...

s. All members of the genus react to spot test as K-, KC+ yellow, with

medulla Medulla or Medullary may refer to: Science * Medulla oblongata, a part of the brain stem * Renal medulla, a part of the kidney * Adrenal medulla, a part of the adrenal gland * Medulla of ovary, a stroma in the center of the ovary * Medulla of t ...

reaction varying from species to species.

Species

Species include: * ''

Xanthoparmelia chlorochroa ''Xanthoparmelia chlorochroa'', known as the tumbleweed shield lichen or ground lichen, is a foliose lichen in the Parmeliaceae family. It is not fixed to a substrate, and blows around in the wind from location to location. Distribution and h ...

'' * '' Xanthoparmelia conspersa'' (''Parmelia conspersa'') * '' Xanthoparmelia cumberlandia'' * ''

Xanthoparmelia lavicola ''Xanthoparmelia lavicola'' is a species of lichen in the family Parmeliaceae that can be found in Mexico north to Arizona and California in the United States. It has also been found in Ecuador. ''Xanthoparmelia lavicola'' grows in dry habitats ...

'' - a foliose (leaf-like) lichen found on

basalt Basalt (; ) is an aphanite, aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the planetary surface, surface of a terrestrial ...

* '' Xanthoparmelia lineola'' * ''

Xanthoparmelia maricopensis ''Xanthoparmelia maricopensis'', the Maricopa rock-shield, is a wide, yellow-green foliose lichen in the Parmeliaceae family. It grows on igneous rock in southwestern North American deserts. Description The thallus is tightly attached to th ...

'' * ''

Xanthoparmelia mexicana ''Xanthoparmelia mexicana'', commonly known as the salted rock-shield, is a foliose lichen in the family Parmeliaceae. It grows in 4–10 cm diameter rosettes of gray-green to yellow-green lobes in arid climates all over the world. Taxon ...

'' * ''

Xanthoparmelia metastrigosa ''Xanthoparmelia metastrigosa'' is a lichen which belongs to the ''Xanthoparmelia'' genus. It is found only in Australia. It is one of the few lichens that is listed as endangered. Description Grows to around 7–12 cm in diameter with i ...

'' * ''

Xanthoparmelia mougeotii ''Xanthoparmelia mougeotii'' is a species of foliose lichen belonging to the family Parmeliaceae. Description The lichen has a foliose thallus that is usually in diameter. It consists of flattened greenish-grey to yellowish-grey lobes (about ...

'' (''Parmelia mougeotii'') * ''

Xanthoparmelia nana ''Xanthoparmelia nana'' is a lichen species in the genus '' Xanthoparmelia'' found in Western Australia. See also * List of lichens of Western Australia * List of ''Xanthoparmelia'' species References nana Nana, Nanna, Na Na or NANA may r ...

'' * ''

Xanthoparmelia pokornyi ''Xanthoparmelia pokornyi'' is a lichen species in the family Parmeliaceae. It contains the depsides gyrophoric acid Gyrophoric acid is a depside that can be found in the lichen ''Cryptothecia rubrocincta'' and in '' Xanthoparmelia pokomyi' ...

'' * ''

Xanthoparmelia subramigera ''Xanthoparmelia subramigera'' is a lichen which belongs to the ''Xanthoparmelia'' genus. Description Grows to around 4-12 cm in diameter with irregularly lobate lobes which are approximately 1.5-4 mm wide. The upper surface of the ...

'' * ''

Xanthoparmelia scabrosa ''Xanthoparmelia scabrosa'', jocularly known as sexy footpath lichen or sexy pavement lichen, is a foliose lichen in the family Parmeliaceae. It tolerates a very wide range of substrata, predominantly rock but also tree bark, roofing tiles, g ...

'' * ''

Xanthoparmelia tinctina ''Xanthoparmelia tinctina'' is a species of lichen from the family Parmeliaceae that can be found in Arizona, California, Northern Africa and Europe. The upper surface is yellow–green, while the bottom surface is brown and flat, measuring in ...

Taxonomy

''Xanthoparmelia'' was originally conceived of as a

section Section, Sectioning or Sectioned may refer to: Arts, entertainment and media * Section (music), a complete, but not independent, musical idea * Section (typography), a subdivision, especially of a chapter, in books and documents ** Section sign ...

of the genus ''

Parmelia Parmelia may refer to: * Parmelia (barque), the vessel that in 1829 transported the first settlers of the British colony of Western Australia * ''Parmelia'' (fungus), a genus of lichens with global distribution * Parmelia, Western Australia Pa ...

'' by Brazilian lichenologist

Edvard August Vainio Edvard August Vainio (born Edvard Lang; 5 August 185314 May 1929) was a Finnish lichenology, lichenologist. His early works on the lichens of Lapland (Finland), Lapland, his three-volume monograph on the lichen genus ''Cladonia'', and, in parti ...

in 1890, to accommodate yellow species with narrow lobes.

Mason Hale Mason Ellsworth Hale, Jr. (September 23, 1929 – April 23, 1990) was one of the most prolific lichenologists of the 20th century. Many of his scholarly articles focused on the taxonomy of the family Parmeliaceae. Hale was one of the first liche ...

considered that the combination of traits including the presence of the cortical pigment

usnic acid Usnic acid is a naturally occurring dibenzofuran derivative found in several lichen species with the formula C18H16O7. It was first isolated by German scientist W. Knop in 1844 and first synthesized between 1933-1937 by Curd and Robertson. Usnic a ...

, 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''. 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

clade A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, ...

s 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 combination ''Combinatio nova'', abbreviated ''comb. nov.'' (sometimes ''n. comb.''), is Latin for "new combination". It is used in taxonomic biology literature when a new name is introduced based on a pre-existing name. The term should not to be confused wi ...

s into ''Xanthoparmelia'' were proposed. 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. ''Karoowia'', a genus that was characterized by features such as its subcrustose growth form and its presence of an arachiform vacuolar body in the

ascospore An ascus (; ) is the sexual spore-bearing cell produced in ascomycete fungi. Each ascus usually contains eight ascospores (or octad), produced by meiosis followed, in most species, by a mitotic cell division. However, asci in some genera or ...

s, was synonymised with ''Xanthoparmelia'' when it was shown that its species cluster in different

s nested within ''Xanthoparmelia''. The genus ''Omphalodiella'', proposed by

Aino Henssen Aino Marjatta Henssen (12 April 1925, Elberfeld – 29 August 2011, Marburg), was a German lichenologist and systematist. Her father, Gottfried Henssen, was a folklorist and her mother was Finns, Finnish. Education and career Henssen began her stu ...

in 1991 to contain the

Patagonia Patagonia () refers to a geographical region that encompasses the southern end of South America, governed by Argentina and Chile. The region comprises the southern section of the Andes Mountains with lakes, fjords, temperate rainforests, and gl ...

n species ''Omphalodiella patagonica'', has since been shown to lie within ''Xanthoparmelia''.

Gallery

Image:Xanthoparmelia_plittii_(EU).jpg, ''

Xanthoparmelia plittii ''Xanthoparmelia plittii'' is a lichen which belongs to the ''Xanthoparmelia'' genus. Description ''Xanthoparmelia plittii'' grows to around 4-10 cm in diameter with irregularly lobate lobes which are approximately 0.5-2 mm wide. Th ...

'' Image:Lichen_reproduction1.jpg, Unidentified ''Xanthoparmelia'' sp. File:Xanthoparmelia subramigera.jpg, ''

'' growing on an asphalt shingle roof in

Maryland Maryland ( ) is a state in the Mid-Atlantic region of the United States. It shares borders with Virginia, West Virginia, and the District of Columbia to its south and west; Pennsylvania to its north; and Delaware and the Atlantic Ocean to ...

, United States

References

{{Taxonbar, from=Q9397450 Lichen genera Lecanorales genera Taxa named by Edvard August Vainio