''Tuckermannopsis'' is a

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 foliose

lichen A lichen ( , ) is a hybrid colony (biology), colony of algae or cyanobacteria living symbiotically among hypha, filaments of multiple fungus species, along with yeasts and bacteria embedded in the cortex or "skin", in a mutualism (biology), m ...

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 ...

Taxonomy

The genus 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 ...

in 1933 by Hungarian lichenologist Vilmos Kőfaragó-Gyelnik. The genus name ''Tuckermannopsis'' honours

Edward Tuckerman Edward Tuckerman (December 7, 1817, in Boston, Massachusetts – March 15, 1886) was an American botanist and professor who made significant contributions to the study of lichens and other alpine plants. He was a founding member of the Natural H ...

(1817–1886), who was an American

botanist Botany, also called plant science, is the branch of natural science and biology studying plants, especially Plant anatomy, their anatomy, Plant taxonomy, taxonomy, and Plant ecology, ecology. A botanist or plant scientist is a scientist who s ...

and

professor Professor (commonly abbreviated as Prof.) is an Academy, academic rank at university, universities and other tertiary education, post-secondary education and research institutions in most countries. Literally, ''professor'' derives from Latin ...

who made significant contributions to the study of

s and other alpine plants. He was a founding member of the Natural History Society of Boston and most of his career was spent at

Amherst College Amherst College ( ) is a Private college, private Liberal arts colleges in the United States, liberal arts college in Amherst, Massachusetts, United States. Founded in 1821 as an attempt to relocate Williams College by its then-president Zepha ...

. '' Tuckermannopsis ciliaris'' was assigned as the

type Type may refer to: Science and technology Computing * Typing, producing text via a keyboard, typewriter, etc. * Data type, collection of values used for computations. * File type * TYPE (DOS command), a command to display contents of a file. * ...

, and at that time, only species. The type species is a lichen, meaning it is erect, foliose, and with

apothecia An ascocarp, or ascoma (: ascomata), is the fruiting body ( sporocarp) of an ascomycete phylum fungus. It consists of very tightly interwoven hyphae and millions of embedded asci, each of which typically contains four to eight ascospores. As ...

and

pycnidia A pycnidium (plural pycnidia) is an asexual fruiting body produced by mitosporic fungi, for instance in the order Sphaeropsidales ( Deuteromycota, Coelomycetes) or order Pleosporales (Ascomycota, Dothideomycetes). It is often spherical or inve ...

( sexual and

asexual Asexual or Asexuals may refer to: *Asexual reproduction **Asexual reproduction in starfish *Asexuality, the lack of sexual attraction to anyone or lack of interest in or desire for sexual activity. **Gray asexuality, the spectrum between asexualit ...

reproductive structures, respectively) that are largely restricted to the margins of the lobes. Starting in the 1980s, the genus became a

wastebasket taxon Wastebasket taxon (also called a wastebin taxon, dustbin taxon or catch-all taxon) is a term used by some taxonomists to refer to a taxon that has the purpose of classifying organisms that do not fit anywhere else. They are typically defined by e ...

containing cetrarioid species of uncertain

taxonomic 280px, Generalized scheme of taxonomy Taxonomy is a practice and science concerned with classification or categorization. Typically, there are two parts to it: the development of an underlying scheme of classes (a taxonomy) and the allocation ...

affinities. In 2001,

Ingvar Kärnefelt Jan Eric Ingvar Kärnefelt (born 1944) is a Swedish lichenologist. Early life and education Kärnefelt was born in Gothenburg, Sweden in 1944. His initial goal in his higher-level studies at University of Cologne in 1966–1967 was to become a ...

and Arne Thell attempted to delimit ''Tuckermannopsis'' based on a combination of

morphology Morphology, from the Greek and meaning "study of shape", may refer to: Disciplines *Morphology (archaeology), study of the shapes or forms of artifacts *Morphology (astronomy), study of the shape of astronomical objects such as nebulae, galaxies, ...

and

molecular phylogeny 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 ...

, although the DNA of only four species was used in the analysis. They accepted seven species in the genus, with distribution centres in western North America and Japan. In 2017, Divakar and colleagues used a recently developed "temporal phylogenetic" approach to identify temporal bands for specific taxonomic ranks in the family Parmeliaceae, suggesting that groups of species that diverged within the time window of 29.45–32.55 million years ago represent genera. They proposed to synonymize ''Tuckermannopsis'' (and several other cetrelioid genera) with ''

Nephromopsis ''Nephromopsis'' is a genus of lichenized fungi within the 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 speci ...

'', so that all the genera within the Parmeliaceae are about the same age. Although some of their proposed taxonomic changes were accepted, the synonymization of the cetrelioid genera with ''Nephromopsis'' was not accepted in a later critical analysis of the temporal phylogenetic technique for use in fungal

systematics Systematics is the study of the diversification of living forms, both past and present, and the relationships among living things through time. Relationships are visualized as evolutionary trees (synonyms: phylogenetic trees, phylogenies). Phy ...

Description

Characteristic of genus ''Tuckermannopsis'' include a

thallus Thallus (: thalli), from Latinized Greek (), meaning "a green shoot" or "twig", is the vegetative tissue of some organisms in diverse groups such as algae, fungi, some liverworts, lichens, and the Myxogastria. A thallus usually names the entir ...

that is either

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 ...

(leafy) or somewhat

fruticose A fruticose lichen is a form of lichen fungi that is characterized by a coral-like shrubby or bushy lichen growth forms, growth structure. It is formed from a symbiotic relationship of a photobiont such as green algae or less commonly cyanobacteri ...

(shrubby) with an upper surface that is brown or greenish in colour; cylindrical asci with a small (a thickened apical region) and broad axial body;

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 that are more or less spherical, measuring 4–8 μm in diameter; the absence of the secondary metabolite

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 and 1937 by Frank H. Curd and Al ...

in the

cortex Cortex or cortical may refer to: Biology * Cortex (anatomy), the outermost layer of an organ ** Cerebral cortex, the outer layer of the vertebrate cerebrum, part of which is the ''forebrain'' *** Motor cortex, the regions of the cerebral cortex i ...

, and the presence of various compounds in the

medulla Medulla (Latin for "marrow") 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 ...

Species

*'' Tuckermannopsis americana'' *'' Tuckermannopsis aurescens'' *'' Tuckermannopsis chlorophylla'' *'' Tuckermannopsis ciliaris'' *'' Tuckermannopsis gilva'' *'' Tuckermannopsis hengduanensis'' *'' Tuckermannopsis merrillii'' *'' Tuckermannopsis microphyllica'' *'' Tuckermannopsis orbata'' *'' Tuckermannopsis subalpina'' *'' Tuckermannopsis ulophylloides'' *'' Tuckermannopsis weii'' The lichen once called ''Tuckermannopsis inermis'' has been transferred to genus ''

Melanohalea ''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 (tiny pores that allow f ...

'', as '' Masonhalea inermis''. ''T. coralligera'' and ''T. fendleri'' have been moved to genus '' Tuckermanella'', created in 2003 to contain cetrarioid lichens previously placed in the "Cetraria fendleri"

species group In biology, a species complex is a group of closely related organisms that are so similar in appearance and other features that the boundaries between them are often unclear. The taxa in the complex may be able to hybridize readily with each oth ...

References

{{Taxonbar, from=Q7851109 Parmeliaceae Lichen genera Lecanorales genera Taxa described in 1933 Taxa named by Vilmos Kőfaragó-Gyelnik