''Caleniella'' is a small

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 ...

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

Gomphillaceae The Gomphillaceae are a family of lichen-forming fungi in the order Graphidales. Species in this family are found mostly in tropical regions. The family underwent a major molecular phylogenetics-led reorganisation in 2023, in which 17 genera were ...

. It comprises two species of leaf-dwelling lichens.

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 2023 by the lichenologists Amanda Xavier-Leite, Marcela Cáceres, and

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 ...

. The name derives from the genus '' Calenia'', where its species were previously classified, with a

diminutive suffix A diminutive is a word obtained by modifying a root word to convey a slighter degree of its root meaning, either to convey the smallness of the object or quality named, or to convey a sense of intimacy or endearment, and sometimes to belittle som ...

(''-iella'') alluding to the relatively small size of its reproductive structures. 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 ...

of the genus is ''Caleniella triseptata'', which was originally described as ''Calenia triseptata'' in 1909.

Molecular A molecule is a group of two or more atoms that are held together by attractive forces known as chemical bonds; depending on context, the term may or may not include ions that satisfy this criterion. In quantum physics, organic chemistry, ...

studies have shown that while ''Caleniella'' is related to the genera '' Caleniopsis'' and '' Aulaxina'', it is distinct enough to warrant its own genus. The main feature distinguishing it from true ''Calenia'' species is its small spores with three cross-walls.

Description

These lichens grow on living leaves, forming a continuous layer on the leaf surface. Their most distinctive features are their 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 ...

), which protrude from the surface and have a cup-like appearance similar to those found in the genus '' Calenia''. These structures are pale in colour with a prominent white outer rim () and a less distinct inner margin. Under the microscope, these lichens show several clear layers of tightly packed, parallel fungal threads. Each reproductive structure typically contains eight , each divided into four cells by three cross-walls (

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 ...

). Unlike many related genera, no specialised reproductive structures called have been observed in ''Caleniella''.

Species

* '' Caleniella maculans'' * '' Caleniella triseptata''

References

{{Taxonbar, from=Q131465641 Gomphillaceae Graphidales genera Lichen genera Taxa described in 2023 Taxa named by Marcela Cáceres Taxa named by Robert Lücking