''Pyrenidium'' 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 lichenicolous (

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 ...

-dwelling)

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 ...

. It is the only genus in the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Pyrenidiaceae. It has 13 species.

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 Finnish lichenologist

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 1865, with '' Pyrenidium actinellum'' assigned as 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 ...

. The family was originally proposed by

Alexander Zahlbruckner Alexander Zahlbruckner (31 May 1860, Svätý Jur – 1938, Vienna) was an Austrian- Hungarian botanist who specialized in the study of lichens. Johann Babtist Zahlbruckner, an earlier Austrian botanist, was his grandfather. From 1878 to 1883 ...

in 1898, and later resurrected for use in 2019. ''Pyrenidium'' was previously classified in Dacampiaceae, but

molecular phylogenetic 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 ...

analysis showed that this family was

polyphyletic A polyphyletic group is an assemblage that includes organisms with mixed evolutionary origin but does not include their most recent common ancestor. The term is often applied to groups that share similar features known as Homoplasy, homoplasies ...

, and that ''Pyrenidium'' originated from a lineage distinct from the genera in that family.

Description

Members of the genus have

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 ...

that are perithecium, perithecioid in form, often with blue-green biological pigment, pigment in the upper wall of the peridium, peridia. Their ascomata are either immersed in the host (biology), host thallus, or bursting through surface (), exposing the upper part of the structure (sometimes still covered by tissue of the host thallus, thalli). They have ascus, asci that contain from four to eight ascospores. Infection by the fungus sometimes causes gall-like malformations of the host thallus.

Species

, Species Fungorum (in the Catalogue of Life) accepts 13 species of ''Pyrenidium'': * '' Pyrenidium actinellum'' * ''Pyrenidium aggregatum'' * ''Pyrenidium borbonicum'' * ''Pyrenidium coccineum'' * ''Pyrenidium cryptotheciae'' * ''Pyrenidium hetairizans'' * ''Pyrenidium hypotrachynae'' * ''Pyrenidium macrosporum'' * ''Pyrenidium octosporum'' * ''Pyrenidium santessonii'' * ''Pyrenidium sporopodiorum'' * ''Pyrenidium ucrainicum'' * ''Pyrenidium zamiae''

References

{{Taxonbar, from=Q10647248 Pleosporales Taxa described in 1865 Dothideomycetes genera Lichenicolous fungi Taxa named by William Nylander (botanist)