''Brigantiaea'' 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 ...

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 ...

-forming

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

in the family

Brigantiaeaceae The Brigantiaeaceae are a family (biology), family of fungi in the order Teloschistales. Species in this family are lichenized with green algae, and are usually found growing on bark. References

Teloschistales Taxa described in 1982 Taxa ...

. The genus was established in 1853 by the Italian botanist Vittore Trevisan and is named after Francesco Briganti, a professor at the

University of Naples The University of Naples Federico II (; , ) is a public university, public research university in Naples, Campania, Italy. Established in 1224 and named after its founder, Frederick II, Holy Roman Emperor, Frederick II, it is the oldest public, s ...

. These lichens are recognised by their bright yellow to orange

fruiting bodies The sporocarp (also known as fruiting body, fruit body or fruitbody) of fungi is a multicellular structure on which spore-producing structures, such as basidia or asci, are borne. The fruitbody is part of the sexual phase of a fungal life cyc ...

that stand out against their crusty, wart-textured surface.

Taxonomy

It 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 the Italian botanist

Vittore Benedetto Antonio Trevisan de Saint-Léon Vittore Benedetto Antonio Trevisan de Saint-Léon (5 June 1818, in Padua – 8 April 1897, in Milan) was an Italian botanist who specialized in cryptogam, cryptogamic flora. He edited the exsiccata ''Lichenotheca Veneta''. During his career, ...

in 1853. Trevisan distinguished ''Brigantiaea'' from other genera in the group by its distinctive spore walls (). In his original description, he included five species in the new genus: ''B. mariae'' (designated as the

type species In International_Code_of_Zoological_Nomenclature, 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 spe ...

), ''B. berteroana'', ''B. tricolor'', ''B. argentea'', and ''B. tristis''. These species were all transfers from the genus ''

Biatora ''Biatora'' is a genus of lichens in the family Ramalinaceae. Originally circumscribed in 1817,Fries EM, Sandberg A. (1817). ''Lichenum dianome nova''. Lund. the genus consists of crustose and squamulose lichens with green algal photobionts, bi ...

''. Trevisan noted that ''B. mariae'' could be found growing on tree bark () in the

Cape of Good Hope The Cape of Good Hope ( ) is a rocky headland on the Atlantic Ocean, Atlantic coast of the Cape Peninsula in South Africa. A List of common misconceptions#Geography, common misconception is that the Cape of Good Hope is the southern tip of Afri ...

region, as recorded by

Johann Franz Drège Johann Fran(t)z Drège (or Jean François Drège) (25 March 1794 Altona, Hamburg, Altona, Duchy of Holstein – 3 February 1881 Altona, Hamburg, Germany), commonly referred to by his standard botanical author abbreviation Drège, was a German horti ...

's collections. The genus name ''Brigantiaea'' honours Francesco Briganti (1802–1865), an Italian botanist and professor at the

Description

''Brigantiaea'' forms a wart-textured crust ( thallus) that spreads thinly over bark or rock. Its internal

green alga The green algae (: green alga) are a group of chlorophyll-containing autotrophic eukaryotes consisting of the phylum Prasinodermophyta and its unnamed sister group that contains the Chlorophyta and Charophyta/ Streptophyta. The land plants ( ...

l partner is single-celled with rounded cells about 6–14 μm across. The lichen's fruit bodies (

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 ...

) are abundant and distinctive: each is surrounded by a thick rim of radiating fungal filaments (the ) and capped by a flat coloured bright yellow, orange, or rusty brown. Under the microscope the supporting

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 o ...

e of the rim are conspicuously broad and brick-like, while the tissue filling the disc () consists of slender, septate

paraphyses Paraphyses are erect sterile filament-like support structures occurring among the reproductive apparatuses of fungi, ferns, bryophytes and some thallophytes. The singular form of the word is paraphysis. In certain fungi, they are part of the f ...

that swell only slightly at their tips. The asci are club-shaped cylinders, usually containing a single

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 ...

. Their tips

stain A stain is a discoloration that can be clearly distinguished from the surface, material, or medium it is found upon. They are caused by the chemical or physical interaction of two dissimilar materials. Accidental staining may make materials app ...

deep blue in iodine—a true

amyloid Amyloids are aggregates of proteins characterised by a fibrillar morphology of typically 7–13 nm in diameter, a β-sheet secondary structure (known as cross-β) and ability to be stained by particular dyes, such as Congo red. In the human ...

reaction—whereas the outer and inner ascus walls remain unstained. Spores are thin-walled, colourless, and : they resemble tiny bricks because multiple cross-walls divide them into a mosaic of chambers. No specialised

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 ...

structures (

conidiomata Conidiomata (singular: Conidioma) are blister-like fruiting structures produced by a specific type of fungus called a coelomycete. They are formed as a means of dispersing asexual spores call conidia, which they accomplish by creating the blister- ...

) have been observed. Chemical tests detect β-orcinol

depside A depside is a type of polyphenolic compound composed of two or more monocyclic aromatic units linked by an ester group. Depsides are most often found in lichens, but have also been isolated from higher plants, including species of the Ericaceae, ...

s in the thallus and the orange pigment

parietin Parietin is the predominant cortical pigment of lichens in the genus '' Caloplaca'', a secondary product of the lichen '' Xanthoria parietina'', and a pigment found in the roots of curled dock (''Rumex crispus''). It has an orange-yellow color ...

concentrated in the apothecial discs, accounting for the vivid surface colours and the rapid purple reaction when treated with

potassium hydroxide Potassium hydroxide is an inorganic compound with the formula K OH, and is commonly called caustic potash. Along with sodium hydroxide (NaOH), KOH is a prototypical strong base. It has many industrial and niche applications, most of which utili ...

solution.

Species

Species Fungorum ''Index Fungorum'' is an international project to index all formal names (Binomial nomenclature, scientific names) in the fungus Kingdom (biology), kingdom. As of 2015, the project is based at the Royal Botanic Gardens, Kew, one of three partn ...

(in the

Catalogue of Life The Catalogue of Life (CoL) 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 Taxono ...

) accept 13 species of ''Brigantiaea''. *'' Brigantiaea chrysosticta'' *'' Brigantiaea crystallina'' – South Korea *'' Brigantiaea fuscolutea'' *'' Brigantiaea leprosa'' *'' Brigantiaea leucoxantha'' *'' Brigantiaea isidiigera'' – Fiji *'' Brigantiaea leprosa'' – Australia *'' Brigantiaea leucoxantha'' *'' Brigantiaea lobulata'' – New Zealand *'' Brigantiaea lobulatisidiata'' – Thailand *'' Brigantiaea lordhowensis'' – Australia *'' Brigantiaea mariae'' *'' Brigantiaea microcarpa'' *'' Brigantiaea phaeomma'' *'' Brigantiaea praetermissa'' – USA *'' Brigantiaea sorediata'' – Japan *'' Brigantiaea subobscurata'' *'' Brigantiaea tricolor''

References

{{Taxonbar, from=Q4967217 Teloschistales Teloschistales genera Lichen genera Taxa described in 1853 Taxa named by Vittore Benedetto Antonio Trevisan de Saint-Léon