''Nyungwea pycnidiata'' is a rare species of

lichen A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship.Opegraphaceae ''Opegraphaceae'' is a family of lichen-forming and lichenicolous fungi in the order Arthoniales. It was originally proposed by German lichenologist Ernst Stizenberger in 1862. It fell into disuse, but was resurrected in a molecular phylogenetic ...

. Found in the North Region of Brazil, it was described as a new species in 2017. It is unique for its adaptation to living on

termite nest Termites are small insects that live in colonies and have distinct castes (eusocial) and feed on wood or other dead plant matter. Termites comprise the infraorder Isoptera, or alternatively the epifamily Termitoidae, within the order Blattod ...

Taxonomy

The species was first

scientifically described A species description is a formal description of a newly discovered species, usually in the form of a scientific paper. Its purpose is to give a clear description of a new species of organism and explain how it differs from species that have be ...

by lichenologists

André Aptroot André Aptroot (Heemskerk, 1961) is a Dutch mycologist and lichenologist. In 1993 he did his PhD at the University of Utrecht under the supervision of Robbert Gradstein (nl). His dissertation was titled "Systematic studies on pyrenocarpous li ...

and Marcela Cáceres in 2015, from a specimen they collected from the Ecotel garden in Fazendinha, (municipality of

Macapá Macapá () is a city in Brazil with a population of 512,902 (2020 estimation). It is the capital of Amapá state in the country's North Region. It is located on the northern channel of the Amazon River near its mouth on the Atlantic Ocean. The c ...

, state of

Amapá Amapá () is one of the 26 states of Brazil. It is in the northern region of Brazil. It is the second least populous state and the eighteenth largest by area. Located in the far northern part of the country, Amapá is bordered clockwise by Fr ...

, Brazil). The lichen was found on a

on a tree in the garden. Aptroot and Cáceres named the species ''pycnidiata'', referring to the distinctive (asexual reproductive structures) of the lichen. This species belongs to the genus ''

Nyungwea ''Nyungwea'' is a genus of lichen-forming fungi in the family Opegraphaceae. It was circumscription (taxonomy), circumscribed in 2006 by Emmanuël Sérusiaux, Eberhard Fischer, and Dorothee Killmann, with ''Nyungwea pallida'' assigned as the typ ...

'', and its identification was aided by

DNA sequencing DNA sequencing is the process of determining the nucleic acid sequence – the order of nucleotides in DNA. It includes any method or technology that is used to determine the order of the four bases: adenine, guanine, cytosine, and thymine. Th ...

, which showed a close association with 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 ...

, ''

Nyungwea pallida ''Nyungwea'' is a genus of lichen-forming fungi in the family Opegraphaceae. It was circumscribed in 2006 by Emmanuël Sérusiaux, Eberhard Fischer, and Dorothee Killmann, with ''Nyungwea pallida'' assigned as the type species. Species * ''Nyu ...

'', found in Africa.

Description

''Nyungwea pycnidiata'' has a greyish-green

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 wer ...

that is thin and dull, resembling clay. Unlike some other lichens, its

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 th ...

(the layer beneath the upper of the thallus) does not have a distinct colour, nor does it contain

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 ...

crystals. The lichen's

hypha A hypha (; ) is a long, branching, filamentous structure of a fungus, oomycete, or actinobacterium. In most fungi, hyphae are the main mode of vegetative growth, and are collectively called a mycelium. Structure A hypha consists of one or ...

e (threadlike fungal cells) are

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 ...

, somewhat brittle, and 2–3

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 Unit ...

wide, giving them a rough texture due to superficial

lecanoric acid Lecanoric acid is a chemical produced by several species of lichen.ubChem - Lecanoric acid"> Lecanoric acid is classified as a polyphenol and a didepside and it functions as an antioxidant. The acid is named after the lichen ''Lecanora''. The acid ...

crystals. The algal partner in the symbiosis is , mostly solitary, and forms a dense . A striking feature of this species is its abundance of pycnidia, which are whitish, (having a textured, bumpy surface), and smooth. These structures measure about 0.1–0.2 mm in diameter and 0.2–0.4 mm in height. The pycnidia are covered at the base by the thallus. The species produces

, simple, and

ellipsoid An ellipsoid is a surface that may be obtained from a sphere by deforming it by means of directional scalings, or more generally, of an affine transformation. An ellipsoid is a quadric surface; that is, a surface that may be defined as the ...

conidia (asexual spores), measuring between 2.5 and 4.0 by 1.5–2.0 μm.

Habitat and distribution

As of the time of its original publication, ''Nyungwea pycnidiata'' is only known to occur at the type locality, on termite nests on trees in a garden in Brazil. It is fairly abundant at this location.

References

{{Taxonbar, from=Q56032849 Arthoniomycetes Lichen species Lichens described in 2017 Lichens of North Brazil Taxa named by André Aptroot Taxa named by Marcela Cáceres