''Biatora'' 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
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
Ramalinaceae
The Ramalinaceae are a family of lichen-forming fungi in the order Lecanorales. First proposed by Carl Adolph Agardh in 1821, the family now comprises 63 genera and about 750 species. Ramalinaceae lichens exhibit diverse growth forms, includin ...
. Originally
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 1817,
[Fries EM, Sandberg A. (1817). ''Lichenum dianome nova''. Lund.] the genus consists of
crustose
Crustose is a Habit (biology), habit of some types of algae and lichens in which the organism grows tightly appressed to a substrate, forming a biological layer. ''Crustose'' adheres very closely to the Substrate (biology), substrates at all poin ...
and
squamulose lichens with
green algal photobiont
A lichen ( , ) is a hybrid colony of algae or cyanobacteria living symbiotically among filaments of multiple fungus species, along with yeasts and bacteria embedded in the cortex or "skin", in a mutualistic relationship. s, biatorine
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 ...
, colorless, simple to 3-septate
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, and bacilliform
pycnospores.
Description
''Biatora'' species are
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 with a spreading ()
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 may appear thin and somewhat membranous in places. The surface is often cracked () and, in species that grow in association with
moss
Mosses are small, non-vascular plant, non-vascular flowerless plants in the taxonomic phylum, division Bryophyta (, ) ''sensu stricto''. Bryophyta (''sensu lato'', Wilhelm Philippe Schimper, Schimp. 1879) may also refer to the parent group bryo ...
es, may be or warted. The thallus is typically creamy white, dull green,
glaucous
''Glaucous'' (, ) is used to describe the pale grey or bluish-green appearance of the surfaces of some plants, as well as in the names of birds, such as the glaucous gull (''Larus hyperboreus''), glaucous-winged gull (''Larus glaucescens''), ...
green, or green-grey and lacks a distinct outer protective layer (). Some species produce
soredia
Soredia are common reproduction, reproductive structures of lichens. Lichens asexual reproduction, reproduce asexually by employing simple fragmentation and production of soredia and isidia. Soredia are powdery propagules composed of fungus, fung ...
, small reproductive that facilitate dispersal. A , the initial fungal layer that some lichens form before developing a full thallus, is absent. The
photosynthetic
Photosynthesis ( ) is a Biological system, system of biological processes by which Photoautotrophism, photosynthetic organisms, such as most plants, algae, and cyanobacteria, convert light energy, typically from sunlight, into the chemical ener ...
partner () is a alga, a group characterized by spherical to broadly
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 cells.
The reproductive structures (
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 , meaning they lack a derived from the lichen thallus itself. They are or closely to the surface and range from weakly to strongly convex. In some species, the apothecia are initially flat with a shallow margin but later become (without a distinct border). Their colour varies widely, including light beige, dark reddish brown, green-grey, bluish green, or khaki. Black apothecia are rare but, when present, have a green or blue tint when wet. Most species lack , the powdery surface coating found on some lichens.
A well-developed (the outer tissue of the apothecium) is present but becomes reflexed over time. It consists of tightly packed, radiating
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 embedded in a gel matrix that remains stable in
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 ...
(K) solution and does not swell. The outer edge may be coated with a thin gel layer. 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 oth ...
, where spores develop, is 30–100 μm tall and typically lacks a distinct (uppermost layer), though some species show pale pigmentation at the top. It does not contain granules or oil droplets and reacts with
iodine
Iodine is a chemical element; it has symbol I and atomic number 53. The heaviest of the stable halogens, it exists at standard conditions as a semi-lustrous, non-metallic solid that melts to form a deep violet liquid at , and boils to a vi ...
(I+),
staining
Staining is a technique used to enhance contrast in samples, generally at the Microscope, microscopic level. Stains and dyes are frequently used in histology (microscopic study of biological tissue (biology), tissues), in cytology (microscopic ...
red-brown when young and blue in older
herbarium
A herbarium (plural: herbaria) is a collection of preserved plant biological specimen, specimens and associated data used for scientific study.
The specimens may be whole plants or plant parts; these will usually be in dried form mounted on a sh ...
specimens. Below the hymenium, the is distinct and slightly opaque due to the presence of ascogenous hyphae (spore-producing structures). The , a supporting tissue beneath the hymenium, consists of interwoven hyphae embedded in a dense gel matrix.
The
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 ...
, sterile filamentous structures within the hymenium, are coherent in KOH, have narrow (0.5–2.5 μm wide), and are mostly unbranched, though occasional branching or connections (
anastomoses
An anastomosis (, : anastomoses) is a connection or opening between two things (especially cavities or passages) that are normally diverging or branching, such as between blood vessels, leaf#Veins, leaf veins, or streams. Such a connection may be ...
) occur. The tips of the paraphyses are slightly swollen, sometimes reaching up to 5 μm in diameter, and rarely bear a distinct cap or hood. The asci, where spores develop, contain eight spores and have a ''Biatora''-type structure. They feature a blue-staining (K/I+) apical dome penetrated from below by a non-staining (K/I–) apical cushion, which is surrounded by a deeply blue-staining zone. The ascus walls themselves do not stain in K/I but are surrounded by an outer layer that reacts red-brown in iodine (I+) and blue in K/I. The ocular chamber, an internal structure within the ascus, is relatively small.
The are colourless, with a shape ranging from ellipsoidal to (thread-like) or (spindle-shaped). They may be aseptate (lacking internal divisions) or have between one and seven
septa
SEPTA, the Southeastern Pennsylvania Transportation Authority, is a regional public transportation authority that operates bus, rapid transit, commuter rail, light rail, and electric trolleybus services for nearly four million people througho ...
. The spores are smooth and do not possess a distinct outer coating ().
Asexual reproduction
Asexual reproduction is a type of reproduction that does not involve the fusion of gametes or change in the number of chromosomes. The offspring that arise by asexual reproduction from either unicellular or multicellular organisms inherit the f ...
occurs via
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 ...
, which are produced in small, flask-shaped reproductive structures called
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 ...
. These structures are within the thallus and have an unpigmented or weakly pigmented wall, similar in colour to the hymenium. The conidia themselves are colourless, aseptate, and (rod-shaped).
Chemically, ''Biatora'' lichens can contain a variety of
secondary metabolite
Secondary metabolites, also called ''specialised metabolites'', ''secondary products'', or ''natural products'', are organic compounds produced by any lifeform, e.g. bacteria, archaea, fungi, animals, or plants, which are not directly involved ...
s, including
gyrophoric acid
Gyrophoric acid is a tridepside. It is a double ester of the orsellinic acid. It can also be found in most of the species of the lichen genera '' Actinogyra'', '' Lasallia'', and '' Umbilicaria'' .
Natural occurrence and biosynthesis
Gyropho ...
and
argopsin
Argopsin, also known as 1-chloropannarin, is a secondary metabolite produced by many lichen species, such as '' Biatora cuprea'' and '' Micarea lignaria''.
Argopsin (also known as 1'-chloropannarin) is a chlorinated depsidone compound first iso ...
, and less commonly, other
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,
depsidone
Depsidones (+ " depside" + "one") are chemical compounds that are sometimes found as secondary metabolites in lichens. They are esters that are both depsides and cyclic ethers. An example is norstictic acid
Norstictic acid is a depsidone produ ...
s,
xanthone
Xanthone is an organic compound with the molecular formula C13H8O2. It is a white solid.
In 1939, xanthone was introduced as an insecticide and it currently finds uses as ovicide for codling moth eggs and as a larvicide. Xanthone is also use ...
s, or
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 ...
. Some species, however, lack detectable secondary metabolites when analysed using
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 ...
.
Species
*''
Biatora alaskana''
*''
Biatora alnetorum''
*''
Biatora amylacea''
– Europe
*''
Biatora appalachensis''
*''
Biatora aureolepra''
*''
Biatora australis''
*''
Biatora bacidioides''
*''
Biatora britannica''
*''
Biatora carneoalbida''
*''
Biatora chrysantha''
*''
Biatora chrysanthoides''
*''
Biatora cuprea''
*''
Biatora cuyabensis''
*''
Biatora efflorescens''
*''
Biatora ementiens''
*''
Biatora epirotica''
*''
Biatora epixanthoides''
*''
Biatora globulosa''
*''
Biatora hafellneri''
*''
Biatora halei''
*''
Biatora hemipolia''
*''
Biatora ivanpisutii''
*''
Biatora kalbii''
*''
Biatora kodiakensis''
*''
Biatora ligni-mollis''
*''
Biatora loekoesiana''
*''
Biatora longispora''
*''
Biatora meiocarpa''
*''
Biatora nobilis''
*''
Biatora oligocarpa''
*''
Biatora oxneri''
*''
Biatora pacifica''
*''
Biatora pallens''
*''
Biatora pausiaca''
*''
Biatora pontica''
*''
Biatora printzenii''
*''
Biatora pseudosambuci''
*''
Biatora pycnidiata''
*''
Biatora radicicola''
*''
Biatora subduplex''
*''
Biatora subhispidula''
*''
Biatora terrae-novae''
*''
Biatora toensbergii''
*''
Biatora vernalis''
*''
Biatora veteranorum''
*''
Biatora vezdana''
The taxon ''Biatora marmorea'', found in
Alaska
Alaska ( ) is a non-contiguous U.S. state on the northwest extremity of North America. Part of the Western United States region, it is one of the two non-contiguous U.S. states, alongside Hawaii. Alaska is also considered to be the north ...
, was proposed as a new species in 2020;
however, it is an
illegitimate name
''Nomen illegitimum'' (Latin for illegitimate name) is a technical term used mainly in botany. It is usually abbreviated as ''nom. illeg.'' Although the International Code of Nomenclature for algae, fungi, and plants uses Latin terms as qualif ...
as it had already been used for a species that is now known as ''
Bagliettoa marmorea''.
References
{{Taxonbar, from=Q4902679
Lecanorales genera
Lichen genera
Taxa named by Elias Magnus Fries
Taxa described in 1817