''Thecographa'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial n ...

of lichen-forming

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

in the family

Graphidaceae The Graphidaceae are a family of lichens in the order Ostropales. Distribution and ecology The vast majority of Graphidaceae species are restricted to the tropics. Most Graphidaceae species are epiphytic (i.e. they grow only on plants). Gene ...

. It has three species of corticolous (bark-dwelling)

script lichen A script lichen, or graphid lichen, is a member of a group of lichens which have spore producing structures that look like writing on the lichen body. The structures are elongated and narrow apothecia called lirellae, which look like short scribble ...

s. The genus was

circumscribed In geometry, the circumscribed circle or circumcircle of a polygon is a circle that passes through all the vertices of the polygon. The center of this circle is called the circumcenter and its radius is called the circumradius. Not every po ...

Abramo Bartolommeo Massalongo Abramo Bartolommeo Massalongo (13 May 1824 – 25 May 1860) was an Italian paleobotanist and lichenologist. He was born in Tregnago in the Province of Verona and took a great interest in botany as a young man. Massalongo joined the faculty of med ...

in 1860. Although Massalongo did not assign a

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( ...

for the genus,

David L. Hawksworth David Leslie Hawksworth (born 1946 in Sheffield, UK) is a British mycologist and lichenologist currently with a professorship in the Universidad Complutense de Madrid in Madrid, Spain and also a Scientific Associate of The Natural History Museum ...

set '' Thecographa prosiliens'' as the type in 1981. Morphological characteristics of the genus include its (fruiting bodies), the lack of a , and the complete of the .

Description

The genus ''Thecographa'' features

apothecia An ascocarp, or ascoma (), 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. Ascocarps are mo ...

(fruiting bodies) that are initially closed and embedded (), but later erupt to become open, elevated, and urn-shaped (). These apothecia often appear almost stalked, and are characteristically flexible, twisted, and angular. They are rarely and sparsely branched. The apothecia are equipped with a distinctive, excipulum that is cup-shaped. This structure is thin but consistent, enveloped by the thallus or tree bark on which the lichen lives. Over time, the covering epidermis may gradually disappear. The of the apothecia is gelatinous, flattened, and tends to lose its colour, supported by a solid, almost papery base known as the . The

asci ASCI or Asci may refer to: * Advertising Standards Council of India * Asci, the plural of ascus, in fungal anatomy * Accelerated Strategic Computing Initiative * American Society for Clinical Investigation * Argus Sour Crude Index * Association of ...

(spore-producing structures) are club-shaped and contain 2-4-8 spores, accompanied by

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 fe ...

(sterile filaments interspersed among the asci). The spores are elliptical or ovoid, (with multiple divisions), initially transparent but becoming cloudy and opaque over time. The thallus of ''Thecographa'' is spread out and irregularly shaped, embedding itself into the .

Species

* '' Thecographa ceramia'' * '' Thecographa crassilabra'' * '' Thecographa prosiliens''

References

{{Taxonbar, from=Q107289461 Graphidaceae Graphidales genera Lichen genera Taxa described in 1860 Taxa named by Abramo Bartolommeo Massalongo