''Cryptoschizotrema'' 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

Graphidaceae The Graphidaceae are a family of lichen-forming fungi in the order Graphidales. The family contains nearly a hundred genera and more than 2000 species. Although the family has a cosmopolitan distribution, most Graphidaceae species occur in tropic ...

. It has two species. 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 2019 by lichenologists

André Aptroot André Aptroot ( Heemskerk, 1961) is a Dutch mycologist and lichenologist. His primary research focus is on biodiversity, particularly tropical lichens, encompassing systematics, floristic surveys, and taxonomic reviews. A prolific research ...

Robert Lücking Robert Lücking (born 1964) is a German lichenologist, known for his extensive research on foliicolous lichens (lichens that live on leaves) and his significant contributions to the taxonomy, ecology, and biodiversity of fungi and lichens. He e ...

, and Marcela Cáceres. The genus name alludes to the similarity in anatomy with '' Schizotrema'' species. This resemblance is due to the partially , concentrically layered, and fissured , which gives the impression that the ''Schizotrema''-like excipulum is concealed beneath a protective layer. 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 ...

was originally described by

William Nylander William Andrew Michael Junior Nylander Altelius (born 1 May 1996) is a Swedish professional ice hockey Forward (ice hockey), forward for the Toronto Maple Leafs of the National Hockey League (NHL). Nylander was selected by the Maple Leafs in t ...

in 1867, as a species of ''

Thelotrema ''Thelotrema'' is a genus of lichen-forming fungi in the family Graphidaceae, the family to which all taxa in the former Thelotremataceae now belong. Members of the genus ''Thelotrema'' are commonly called barnacle lichens. Description ''Thelo ...

''.

Description

The

ascomata An ascocarp, or ascoma (: ascomata), is the fruiting body (sporocarp (fungi), sporocarp) of an ascomycete phylum fungus. It consists of very tightly interwoven hyphae and millions of embedded ascus, asci, each of which typically contains four to ...

of ''Cryptoschizotrema'' lichens are immersed- and rounded, with the concealed beneath a narrow pore. The is hidden by a whitish thalline layer, and when abraded, it reveals brown to black fissured that form concentric layers in older specimens. Notably, a is absent in this genus. The of ''Cryptoschizotrema'' is , displaying a dark brown colour that may partially towards its apex. As the ascomata mature, the excipulum develops distinct layers or striations. , however, are not present. 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 ...

of this lichen is transparent, featuring unbranched . are typically found in quantities of one to two, though occasionally up to four per

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 ...

. These ascospores are , measuring up to 100 by 30

μm The micrometre (Commonwealth English as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American English), also commonly known by the non-SI term micron, is a unit of length in the International System ...

, and have an oblong to

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 ...

shape. The , with relatively thin walls and

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 ...

, along with angular , contribute to the ascospores' colourless appearance. Additionally, they are I-negative, indicating their non-

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 ...

nature. The secondary chemistry of the genus is characterized by the presence of

psoromic acid Psoromic acid is a β-orcinol depsidone with the molecular formula C18H14O8. Psoromic acid inhibits herpes simplex viruses type 1 and type 2. Furthermore, it inhibits the RabGGTase. Psoromic acid occurs in antarctic lichens A lichen ( , ) ...

, which causes the

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 ...

to display a P+ (yellow) reaction with standard chemical spot tests.

Species

Species in this genus occur in Central and South America. * '' Cryptoschizotrema cryptotrema'' * '' Cryptoschizotrema minus''

References

{{Taxonbar, from=Q117186618 Graphidaceae Lichen genera Graphidales genera Taxa described in 2019 Taxa named by André Aptroot Taxa named by Marcela Cáceres Taxa named by Robert Lücking