''Bellemerea'' 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 ...

saxicolous This glossary of mycology is a list of definitions of terms and concepts relevant to mycology, the study of fungi. Terms in common with other fields, if repeated here, generally focus on their mycology-specific meaning. Related terms can be found ...

(rock-dwelling)

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

s in the family

Lecideaceae The Lecideaceae are a family (biology), family of lichen-forming fungi in the order Lecideales. It contains about 30 genus, genera and roughly 250 species. A major distinguishing characteristic of the family is the form of the ascomata, fruit ...

. These lichens form tough, crusty patches on hard rock surfaces, often appearing as a mosaic of small angular blocks in colours ranging from white and grey to brown. The genus includes nine species found primarily in

mountainous A mountain is an elevated portion of the Earth's crust, generally with steep sides that show significant exposed bedrock. Although definitions vary, a mountain may differ from a plateau in having a limited summit area, and is usually higher t ...

and

polar regions The polar regions, also called the frigid geographical zone, zones or polar zones, of Earth are Earth's polar ice caps, the regions of the planet that surround its geographical poles (the North Pole, North and South Poles), lying within the pol ...

where they help colonize bare rock surfaces in harsh environments.

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 1984 by

Josef Hafellner Josef Hafellner (1951– ) is an Austrian mycologist and lichenologist. He was awarded the Acharius Medal in 2016 for his lifetime contributions to lichenology. Before his retirement, he was a professor at the Karl-Franzens-Universität in Graz ...

and

Claude Roux Claude Roux is a French lichenologist, mycologist and Esperantist. He has co-authored books about the identification of lichens written in Esperanto. Career From 1969 to 1975, Roux taught biology and geology in a secondary school. From 1975 he w ...

, with '' B. alpina'' 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 ...

. The generic name honours the French lichenologist André Henri Bellemère (1927–2014).

Description

''Bellemerea'' species form firmly attached, crust-like colonies on hard, often

siliceous rock Siliceous rocks are sedimentary rocks that have silica (SiO2) as the principal constituent. The most common siliceous rock is chert; other types include diatomite. They commonly form from silica-secreting organisms such as radiolarians, diatoms, o ...

. Seen close up, the surface is broken into angular blocks or low warts () that may be scattered or jammed tightly together.

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 ...

colour ranges from chalk-white through pale grey to

ochre Ochre ( ; , ), iron ochre, or ocher in American English, is a natural clay earth pigment, a mixture of ferric oxide and varying amounts of clay and sand. It ranges in colour from yellow to deep orange or brown. It is also the name of the colou ...

or even rusty brown, and a thin black "seam" of

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 (the ) can usually be seen edging the colony. The internal algal partner is a green alga whose cells are frequently

ellipsoid An ellipsoid is a surface that can be obtained from a sphere by deforming it by means of directional Scaling (geometry), scalings, or more generally, of an affine transformation. An ellipsoid is a quadric surface; that is, a Surface (mathemat ...

al; in many specimens the runs unbroken beneath the fruiting bodies. When a drop of iodine is applied, the inner white layer (

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 ...

) turns a deep violet—an easy field test for the genus. The sexual structures are small black discs (

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 ...

) that start buried in the areoles but often expand until they fill almost the whole surface of a single block. The are flat to shallowly cup-shaped and bordered by a wafer-thin that seldom rises above the surface. The usual inner cup wall () is extremely thin or missing altogether, so the disc appears to pass straight into the surrounding crust. Under the microscope the spore layer (

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 oth ...

) is threaded by branched, cross-linked

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 ...

whose tips swell slightly and carry a faint brown cap; the layer below () is colourless. Each club-shaped

ascus An ascus (; : asci) 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 gen ...

contains eight smooth, colourless

ascospores 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 of fungi. After two parental nuclei fuse, the ascus undergoes meiosis (halving of ...

that are single-celled but sometimes show a faint ghost

septum In biology, a septum (Latin language, Latin for ''something that encloses''; septa) is a wall, dividing a Body cavity, cavity or structure into smaller ones. A cavity or structure divided in this way may be referred to as septate. Examples Hum ...

; a distinctive iodine-positive inner wall and a clear gelatinous envelope surround each spore. Minute, sunken

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 ...

release short, rod-shaped

conidia A conidium ( ; : conidia), sometimes termed an asexual chlamydospore or chlamydoconidium (: chlamydoconidia), is an asexual, non- motile spore of a fungus. The word ''conidium'' comes from the Ancient Greek word for dust, ('). They are also ...

for

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 ...

spread, and

thin-layer chromatography Thin-layer chromatography (TLC) is a chromatography technique that separates components in non-volatile mixtures. It is performed on a TLC plate made up of a non-reactive solid coated with a thin layer of adsorbent material. This is called the sta ...

detects

norstictic acid Norstictic acid is a depsidone produced as a secondary metabolites in lichens. The compound contains both an aldehyde carbonyl group and an adjacent hydroxyl In chemistry, a hydroxy or hydroxyl group is a functional group with the chemical fo ...

in several members of the genus. The combination of spores with an iodine-blue perispore, colourless cup wall and colourless hypothecium distinguishes ''Bellemerea'' from superficially similar crustose genera such as ''

Amygdalaria ''Amygdalaria'' is a genus of lichen-forming fungi in the family Lecideaceae. These lichens are typically found growing as crustose lichen, crusts on siliceous rocks in arctic and alpine environments. Members of this genus form crustose thallus ...

'', ''

Aspicilia ''Aspicilia'' (sunken disk lichen) is a genus of mostly crustose lichen, crustose areolate lichen, areolate lichens that grow on rock. Most members have black apothecia discs that are slightly immersed in the areolas, hence the List of common na ...

'' and ''

Porpidia ''Porpidia'' is a genus of crustose lichens in the family Lecideaceae. ''Porpidia'' species primarily inhabit siliceous rocks, pebbles, and stonework, with rare occurrences on bark, wood, and compacted soil. The thallus, or body of the lichen, ...

''.

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 nine species of ''Bellemerea'': *''

Bellemerea alpina ''Bellemerea alpina'', the brown sunken disk lichen, is a white to pale tan, thick crustose lichen, crustose areolate lichen that grows on rock in the mountains worldwide. It grows in arctic-alpine habitats in Eurasia, North America (south to Cal ...

'' *'' Bellemerea cinereorufescens'' *'' Bellemerea diamarta'' *'' Bellemerea elegans'' *'' Bellemerea pullata'' *'' Bellemerea sanguinea'' *'' Bellemerea subcandida'' *'' Bellemerea subnivea'' *'' Bellemerea subsorediza''

References

{{Taxonbar, from=Q4883792 Lecideales Lecideales genera Lichen genera Taxa described in 1984 Taxa named by Josef Hafellner Taxa named by Claude Roux