''Nitidochapsa'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial n ...

of lichen-forming

fungi A fungus (plural, : fungi or funguses) is any member of the group of Eukaryote, eukaryotic organisms that includes microorganisms such as yeasts and Mold (fungus), molds, as well as the more familiar mushrooms. These organisms are classified ...

in the family

Graphidaceae The Graphidaceae are a family of lichens in the order Ostropales. Distribution and ecology The vast majority of Graphidaceae species are restricted to the tropics. Most Graphidaceae species are epiphytic (i.e. they grow only on plants). Gene ...

. It has five species of corticolous (bark-dwelling),

crustose lichen Crustose lichens are lichens that form a crust which strongly adheres to the substrate (soil, rock, tree bark, etc.), making separation from the substrate impossible without destruction. The basic structure of crustose lichens consists of a cor ...

Taxonomy

The genus was

circumscribed In geometry, the circumscribed circle or circumcircle of a polygon is a circle that passes through all the vertices of the polygon. The center of this circle is called the circumcenter and its radius is called the circumradius. Not every po ...

in 2013 by the lichenologists Sittiporn Parnmen,

Robert Lücking Robert Lücking (born 1964) is a German lichenologist. He is a leading expert on foliicolous lichens–lichens that live on leaves. Life and career Born in Ulm in 1964, Lücking earned both his master's (1990) and PhD degree (1994) at the Univer ...

, and

H. Thorsten Lumbsch Helge Thorsten Lumbsch (born 1964) is a German-born lichenologist living in the United States. His research interests include the phylogeny, taxonomy, and phylogeography of lichen-forming fungi; lichen diversity; lichen chemistry and chemotax ...

. The

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen( ...

is '' N. leprieurii'', originally described in 1855 from specimens collected in French Guiana, as a member of ''

Sticta ''Sticta'' is a genus of lichens in the family Peltigeraceae. The genus has a widespread distribution, especially in tropical areas, and includes about 114 species. These lichens have a leafy appearance, and are colored brown or black. ''Sticta' ...

''.

Description

The

thallus Thallus (plural: 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. Many of these organisms ...

of ''Nitidochapsa'' is continuous and can have a smooth to uneven surface, characterised by an olive-brown colour. When observed in a cross-section, the thallus of ''Nitidochapsa'' has a dense upper

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 ...

composed of tightly packed cells () and an irregular that partially lies beneath the bark's outer layer (endoperidermal). This genus typically lacks or rarely forms clusters of

calcium oxalate Calcium oxalate (in archaic terminology, oxalate of lime) is a calcium salt of oxalic acid with the chemical formula . It forms hydrates , where ''n'' varies from 1 to 3. Anhydrous and all hydrated forms are colorless or white. The monohydrate ...

, a common crystalline compound in many lichens. The

apothecia An ascocarp, or ascoma (), 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. Ascocarps are mo ...

(fruiting bodies) ''Nitidochapsa'' are angular-rounded and emerge from the thallus (). The of the apothecia is light brown and covered with a fine white powder (white-), while the around the disc is indistinct. The of the apothecia has 5 to 8 recurved that are felty and white. A , or central pillar-like structure commonly found in some lichens' apothecia, is absent in this genus. The (tissue surrounding the apothecia) is prosoplectenchymatous and varies in colour from

hyaline A hyaline substance is one with a glassy appearance. The word is derived from el, ὑάλινος, translit=hyálinos, lit=transparent, and el, ὕαλος, translit=hýalos, lit=crystal, glass, label=none. Histopathology Hyaline cartilage is ...

(translucent) to pale brown. ''Nitidochapsa'' also features , which are hair-like structures around the apothecial margin. The

hymenium The hymenium is the tissue layer on the hymenophore of a fungal fruiting body where the cells develop into basidia or asci, which produce spores. In some species all of the cells of the hymenium develop into basidia or asci, while in others som ...

, the spore-producing layer, is clear, and the (sterile filaments in the hymenium) are unbranched. Each

ascus 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 o ...

(spore-bearing cell) contains eight . These spores are 3-septate (divided into three compartments by

septa The Southeastern Pennsylvania Transportation Authority (SEPTA) is a regional public transportation authority that operates transit bus, bus, rapid transit, commuter rail, light rail, and electric trolleybus services for nearly 4 million people ...

), measuring 12–16 by 5–6

μm The micrometre ( international spelling as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American spelling), also commonly known as a micron, is a unit of length in the International System of Uni ...

, oblong in shape, with thickened septa and lens-shaped (lenticular) . The spores are dark brown and turn violet-blue with iodine

staining Staining is a technique used to enhance contrast in samples, generally at the microscopic level. Stains and dyes are frequently used in histology (microscopic study of biological tissues), in cytology (microscopic study of cells), and in ...

(I+ violet-blue reaction). In terms of chemistry, ''Nitidochapsa'' does not produce any

secondary metabolite Secondary metabolites, also called specialised metabolites, toxins, secondary products, or natural products, are organic compounds produced by any lifeform, e.g. bacteria, fungi, animals, or plants, which are not directly involved in the no ...

Species

Species Fungorum ''Index Fungorum'' is an international project to index all formal names ( scientific names) in the fungus kingdom. the project is based at the Royal Botanic Gardens, Kew, one of three partners along with Landcare Research and the Institute of ...

(in the

Catalogue of Life The Catalogue of Life is an online database that provides an index of known species of animals, plants, fungi, and microorganisms. It was created in 2001 as a partnership between the global Species 2000 and the American Integrated Taxonomic I ...

) accepts five species of ''Nitidochapsa'': * '' Nitidochapsa aggregata'' * '' Nitidochapsa leprieurii'' * '' Nitidochapsa phlyctidea'' * '' Nitidochapsa siamensis'' – Thailand * '' Nitidochapsa stictoides''

References

{{Taxonbar, from=Q21214863 Graphidaceae Graphidales genera Lichen genera Taxa described in 2013 Taxa named by Robert Lücking Taxa named by Helge Thorsten Lumbsch Taxa named by Sittiporn Parnmen