''Culbersonia'' is a fungal

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 ...

in the family

Caliciaceae The Caliciaceae are a family (taxonomy), family of mostly lichen-forming fungus, fungi belonging to the class (taxonomy), class Lecanoromycetes in the division (mycology), division Ascomycota. Although the family has had its classification chan ...

. This is a

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unisp ...

genus, containing the single

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 ...

''Culbersonia nubila'' (formerly called ''Culbersonia americana''). This species, which grows on trees and rocks, is found in dry

subtropical The subtropical zones or subtropics are geographical zone, geographical and Köppen climate classification, climate zones immediately to the Northern Hemisphere, north and Southern Hemisphere, south of the tropics. Geographically part of the Ge ...

regions of the world, particularly in Africa and Central America.

Taxonomy

The genus ''Culbersonia'' was

circumscribed In geometry, a circumscribed circle for a set of points is a circle passing through each of them. Such a circle is said to ''circumscribe'' the points or a polygon formed from them; such a polygon is said to be ''inscribed'' in the circle. * Circum ...

by Theodore Esslinger in 2000, to contain a lichen he collected from

Arizona Arizona is a U.S. state, state in the Southwestern United States, Southwestern region of the United States, sharing the Four Corners region of the western United States with Colorado, New Mexico, and Utah. It also borders Nevada to the nort ...

that he named ''Culbersonia americana''. The genus name of ''Culbersonia'' is in honour of Chicita Frances 'Nan' Culberson, (b.1931), an American botanist (Mycology und Lichenology), who worked as a botanical researcher at

Duke University Duke University is a Private university, private research university in Durham, North Carolina, United States. Founded by Methodists and Quakers in the present-day city of Trinity, North Carolina, Trinity in 1838, the school moved to Durham in 1 ...

in Durham/North Carolina and William Louis "Bill" Culberson (1929–2003), an American lichenologist. As they were "longtime friends and mentors" of Esslinger. After ''Culbersonia americana'' was published, it was determined that the Arizona species was the same as one previously described from Africa in 1980 by

Roland Moberg Roland (; ; or ''Rotholandus''; or ''Rolando''; died 15 August 778) was a Franks, Frankish military leader under Charlemagne who became one of the principal figures in the literary cycle known as the Matter of France. The historical Roland w ...

, called ''Pyxine nubila''. A

new combination In Taxonomy (biology), biological taxonomy, a combinatio nova (abbreviated comb. nov. or n. comb.) refers to the formal renaming of an organism's scientific name when it is transferred to a different genus, reclassified within a different specie ...

was made in a 2002 publication, and the name ''Culbersonia nubila'' was proposed. ''Culbersonia'' was until recently thought to belong to the

Physciaceae The Physciaceae are a family of mostly lichen-forming fungi belonging to the class Lecanoromycetes in the division Ascomycota. A 2016 estimate placed 19 genera and 601 species in the family. Description The Physiaceae family includes various ...

due to morphological similarities with some of the genera in that family. Recent (2019)

molecular phylogenetic 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 ...

analysis showed that it forms a

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 ...

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 ...

with ''

Pyxine ''Pyxine'' is a genus of foliose lichens in the family Caliciaceae. The genus has a widespread distribution in tropical regions. The presence or absence of the compound lichexanthone is a character used in classifying ''Pyxine '' species; about ...

'' and '' Diplotomma'', both of which are in the Caliciaceae. These three genera are morphologically distinguished from the other Caliciaceae by the appressed

foliose 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 lichen growth forms, growth forms of lichens. It typically has distinct upper and lo ...

growth form and the absence of a mazaedium (a fruit body consisting of a powdery mass of free

ascospore In fungi, an ascospore is the sexual spore formed inside an ascus—the sac-like cell that defines the division Ascomycota, the largest and most diverse Division (botany), division of fungi. After two parental cell nucleus, nuclei fuse, the ascu ...

s).

Habitat and distribution

''Culbersonia nubila'' grows on trees and rocks. It is found in dry

regions of the world, particularly in Africa and Central America.

References

{{Taxonbar, from=Q5192859, from2=Q10463446 Caliciales Lichen genera Caliciales genera Taxa described in 2000 Taxa named by Theodore Lee Esslinger