''Gondwania'' 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 subfamily Xanthorioideae of the family

Teloschistaceae The Teloschistaceae are a large family (biology), family of mostly lichen-forming fungi belonging to the class (taxonomy), class Lecanoromycetes in the division (botany), division Ascomycota. The family has a cosmopolitan distribution, althoug ...

. It comprises five species of

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 ...

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 ...

by the lichenologists Ulrik Søchting, Patrik Frödén, and Ulf Arup in 2013. 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 ...

is '' G. cribrosa'', a species that was first named ''Polycauliona cribrosa'' by Auguste-Marie Hue in 1909. The genus name refers to the ancestral supercontinent

Gondwana Gondwana ( ; ) was a large landmass, sometimes referred to as a supercontinent. The remnants of Gondwana make up around two-thirds of today's continental area, including South America, Africa, Antarctica, Australia (continent), Australia, Zea ...

, reflecting the predominantly Southern Hemisphere distribution of the genus. ''Gondwania'' belongs to the subfamily Xanthorioideae within the family Teloschistaceae.

Molecular phylogenetics Molecular phylogenetics () is the branch of phylogeny that analyzes genetic, hereditary molecular differences, predominantly in DNA sequences, to gain information on an organism's evolutionary relationships. From these analyses, it is possible to ...

analyses place ''Gondwania'' in a

clade In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach t ...

with several other Southern Hemisphere genera, including '' Austroplaca'', ''

Cerothallia ''Cerothallia'' is a genus of crustose lichens in the family Teloschistaceae. It has four species, all of which occur in the Southern Hemisphere. The genus was circumscribed in 2013 by Ulf Arup, Patrik Frödén, and Ulrik Søchting, with '' Cerot ...

'', and '' Transdrakea''. Within this clade, ''Gondwania'' forms a well-supported

monophyletic In biological cladistics for the classification of organisms, monophyly is the condition of a taxonomic grouping being a clade – that is, a grouping of organisms which meets these criteria: # the grouping contains its own most recent co ...

group.

Description

''Gondwania'' species are grow on rock, with one exception that is

corticolous 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 ...

(growing on bark). They exhibit a variety of

growth forms Plant life-form schemes constitute a way of classifying plants alternatively to the ordinary species-genus-family scientific classification. In colloquial speech, plants may be classified as trees, shrubs, herbs (forbs and graminoids), etc. The sci ...

: , somewhat

fruticose A fruticose lichen is a form of lichen fungi that is characterized by a coral-like shrubby or bushy lichen growth forms, growth structure. It is formed from a symbiotic relationship of a photobiont such as green algae or less commonly cyanobacteri ...

, or

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 ...

. The thalli of some species feature

pseudocyphella Pseudocyphellae (singular ''pseudocyphella'') are structures in lichens that appear as tiny pores on the outer surface (the cortex) of the lichen. They are caused when there is a break in the cortex of the lichen, and the medullary hyphae extend ...

e, which are small pores in the upper cortex that appear as slightly paler spots on the surface.

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 ...

(fruiting bodies) in ''Gondwania'' are typically to in form, ranging from 0.5 to 6 mm in diameter. The colour varies from orange to brownish-orange. The margin is often well-developed and can be pseudocyphellate in some species. Microscopically, ''Gondwania'' species have asci of the ''

Teloschistes ''Teloschistes'' is a genus 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 cort ...

''-type, each containing eight spores. The ascospores are (with two cells divided by a

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 ...

) and generally

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 ...

. Spore sizes and septum widths vary among species and can be diagnostic features. Species contain

lichen product Lichen products, also known as lichen substances, are organic compounds produced by a lichen. Specifically, they are secondary metabolites. Lichen products are represented in several different chemical classes, including terpenoids, orcinol deri ...

s characteristic of A, with parietin being the dominant

anthraquinone Anthraquinone, also called anthracenedione or dioxoanthracene, is an aromatic hydrocarbon, aromatic organic compound with formula . Several isomers exist but these terms usually refer to 9,10-anthraquinone (IUPAC: 9,10-dioxoanthracene) wherein th ...

(comprising 92–95% of the total). All yellow, orange or reddish-pigmented parts of the lichen turn purple when exposed to

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 (K+ purple reaction). '' Cerothallis'', '' Austroplaca'', and ''Transdrakea'' are closely related genera in the Teloschistaceae. ''Gondwania'' has a Southern Hemisphere distribution, occurring in Antarctica, southern Australia (particularly Tasmania), New Zealand, and

Patagonia Patagonia () is a geographical region that includes parts of Argentina and Chile at the southern end of South America. The region includes the southern section of the Andes mountain chain with lakes, fjords, temperate rainforests, and glaciers ...

, including the Falkland Islands. This distribution pattern suggests an origin in the ancient Gondwana supercontinent, with subsequent diversification following the breakup of the landmass.

Species

* '' Gondwania cribrosa'' –

Tasmania Tasmania (; palawa kani: ''Lutruwita'') is an island States and territories of Australia, state of Australia. It is located to the south of the Mainland Australia, Australian mainland, and is separated from it by the Bass Strait. The sta ...

; New Zealand * '' Gondwania inclinans'' – New Zealand * '' Gondwania joannae'' – Antarctica * '' Gondwania sejongensis'' * '' Gondwania sublobulata'' – South America The proposed

taxon In biology, a taxon (back-formation from ''taxonomy''; : taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular name and ...

''Gondwania regalis'' has since been transferred to a different genus and is now known as '' Polycauliona regalis''.

References

{{Taxonbar, from=Q25818975 Teloschistales Teloschistales genera Lichen genera Taxa described in 2013 Taxa named by Ulrik Søchting Taxa named by Patrik Frödén Taxa named by Ulf Arup