''Platismatia'' is

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of medium to large

foliose lichen A foliose lichen is a lichen with flat, leaf-like , which are generally not firmly bonded to the substrate on which it grows. It is one of the three most common growth forms of lichens. It typically has distinct upper and lower surfaces, each o ...

s 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'' ( 82 ...

. The genus is widespread and contains 11 species. They resemble many other genera of foliose lichens in the Parmeliaceae, particularly ''

Parmotrema ''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. Members of the genus ...

'', ''

Cetrelia ''Cetrelia'' is a genus of leafy lichens in the large family Parmeliaceae. They are commonly known as sea-storm lichens, alluding to the wavy appearance of their lobes. The name of the genus, circumscribed in 1968 by the husband and wife li ...

'', and '' Asahinea''. Most species are found in forests on the trunks and branches of conifer trees, although some species grow on rocks.Brodo, I. M., S. D. Sharnoff, and S. Sharnoff. 2001. Lichens of North America. Yale University Press: New Haven. Species of ''Platismatia'' can be used to produce an orange-brown, yellow-brown, or brown dye,Brough, S. G. 1984. Dye characteristics of British Columbia forest lichens. Syesis 17: 81-94. and at least one species was traditionally used to dye wool in Europe. Uphof, J. C. T. 1959. Dictionary of Economic Plants. Hafner Publishing Co.: New York.

Taxonomy

The genus ''Platismatia'' was historically classified within ''

Cetraria ''Cetraria'' is a genus of fruticose lichens that associate with green algae as photobionts. Most species are found at high latitudes, occurring on sand or heath, and are characterised by their "strap-like" form with spiny edges. The lobes can ...

'' by

Erik Acharius Erik Acharius (10 October 1757 – 14 August 1819) was a Swedish botanist who pioneered the Taxonomy (biology), taxonomy of lichens and is known as the "father of lichenology". Acharius was famously the last pupil of Carl Linnaeus. Life Ac ...

in the early 1800s, along with several other superficially similar taxa that were later moved to other genera like '' Asahinea'' and ''

''. While

molecular phylogenetics Molecular phylogenetics () is the branch of phylogeny that analyzes genetic, hereditary molecular differences, predominantly in DNA sequences, to gain information on an organism's evolutionary relationships. From these analyses, it is possible to ...

studies since the 2010s have challenged many traditional classifications of parmelioid lichens, particularly those formerly placed in ''Cetraria'', ''Platismatia''s historical delimitation has been consistently supported by molecular evidence as both

monophyletic In biological cladistics for the classification of organisms, monophyly is the condition of a taxonomic grouping being a clade – that is, a grouping of organisms which meets these criteria: # the grouping contains its own most recent co ...

and well-defined. As of 2023, there are 11 accepted species within the genus, with seven occurring in North America north of Mexico. A comprehensive molecular phylogenetic study published in 2023 examined relationships within ''Platismatia'' using both newly generated and existing

internal transcribed spacer Internal transcribed spacer (ITS) is the spacer DNA situated between the small-subunit ribosomal RNA (rRNA) and large-subunit rRNA genes in the chromosome or the corresponding transcribed region in the polycistronic rRNA precursor transcript. ...

(ITS) sequence data. This study confirmed the monophyly of most currently recognized species, including ''P. wheeleri'', which was described in 2011 and had previously lacked molecular confirmation. The study revealed some taxonomically interesting patterns within the genus. The widespread ''P. glauca'' was found to contain two distinct, highly supported

clade In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach t ...

s that showed no apparent morphological or geographic differences. Additionally, the western North American endemics ''P. herrei'' and ''P. stenophylla'' were not recovered as reciprocally monophyletic, suggesting they may represent a case of recent

speciation Speciation is the evolutionary process by which populations evolve to become distinct species. The biologist Orator F. Cook coined the term in 1906 for cladogenesis, the splitting of lineages, as opposed to anagenesis, phyletic evolution within ...

or possibly

conspecific Biological specificity is the tendency of a characteristic such as a behavior or a biochemical variation to occur in a particular species. Biochemist Linus Pauling stated that "Biological specificity is the set of characteristics of living organism ...

taxa requiring further investigation. Reproductive modes appear to play an important role in the evolution and diversification of ''Platismatia'' species. The genus includes examples of both sexually and asexually reproducing species, with some evidence suggesting that sexual reproduction can evolve from primarily asexual ancestors. Species producing asexual

propagule In biology, a propagule is any material that functions in propagating an organism to the next stage in its life cycle, such as by dispersal. The propagule is usually distinct in form from the parent organism. Propagules are produced by organisms ...

s (either

isidia An isidium (plural: isidia) is a tiny, wart- or finger-like outgrowth on the thallus surface of certain lichen species. It is one of two principal types of vegetative reproduction, vegetative reproductive structures in lichens, the other being ...

soredia Soredia are common reproduction, reproductive structures of lichens. Lichens asexual reproduction, reproduce asexually by employing simple fragmentation and production of soredia and isidia. Soredia are powdery propagules composed of fungus, fung ...

) generally show larger geographic ranges than their sexually reproducing relatives, though exceptions exist.

Species

* ''

Platismatia erosa ''Platismatia erosa'' is a species of corticolous (bark-dwelling), foliose lichen in the family Parmeliaceae. Found in Asia, it was formally described as a new species in 1968 by William and Chicita Culberson. The species epithet ''erosa'' refer ...

'' * ''

Platismatia formosana ''Platismatia formosana'' is a species of corticolous (bark-dwelling), foliose lichen in the family Parmeliaceae. Found in the mountains of Taiwan, it was first formally described as a species of '' Cetraria'' in 1933 by Alexander Zahlbruckner. W ...

'' * ''

Platismatia glauca ''Platismatia glauca'' is a common and widespread species of corticolous (bark-dwelling), foliose lichen in the family Parmeliaceae. This distinctive lichen forms pale to dull grey patches measuring 1–15 centimetres across, with wavy, irregular ...

'' * ''

Platismatia herrei ''Platismatia herrei'' is a species of corticolous (bark-dwelling), foliose lichen in the family Parmeliaceae. It was first formally described as a species of '' Cetraria'' in 1968 by lichenologist Henry Imshaug. William and Chicita Culberso ...

'' * ''

Platismatia interrupta ''Platismatia interrupta'' is a species of foliose lichen in the family Parmeliaceae. Found in southern Russian Far East, and Japan, it was formally described as a new species in 1968 by William and Chicita Culberson. The species epithet ''inter ...

'' * ''

Platismatia lacunosa ''Platismatia lacunosa'' is a species of corticolous (bark-dwelling), foliose lichen in the family Parmeliaceae. Known predominantly from western North America, it reproduces primarily through sexual means, which is uncommon in the genus. The spe ...

'' * ''

Platismatia norvegica ''Platismatia'' is genus of medium to large foliose lichens in the family Parmeliaceae. The genus is widespread and contains 11 species. They resemble many other genera of foliose lichens in the Parmeliaceae, particularly ''Parmotrema'', ''Cetre ...

'' * ''

Platismatia regenerans ''Platismatia regenerans'' is a species of corticolous (bark-dwelling), foliose lichen in the family Parmeliaceae. Found in Borneo, it was formally described as a new species in 1968 by William and Chicita Culberson. The type specimen was collec ...

'' * '' Platismatia stenophylla'' * '' Platismatia tuckermanii'' * '' Platismatia wheeleri''

Gallery

Image:Platismatia glauca 060408.jpg, ''Platismatia glauca'', Schwäbisch-Fränkische Waldberge, Germany Image:Platismatia glauca 010108.jpg, ''Platismatia glauca'', Schwäbisch-Fränkische Waldberge, Germany File:Platismatia wheeleri col oct 2012, imaged feb2013 GEIDE.tif, ''Platismatia wheeleri'', Underside of thallus; Yelm, Washington, United States File:Platismatia tuckermanii NS.jpg, ''Platismatia tuckermanii'', on Spruce branch in Nova Scotia, Canada

References

{{Taxonbar, from=Q3373270 Parmeliaceae Lichen genera Lecanorales genera Taxa described in 1968 Taxa named by Chicita F. Culberson Taxa named by William Louis Culberson