The Taphrinomycotina are one of three subdivisions constituting the

Ascomycota Ascomycota is a phylum of the kingdom Fungi that, together with the Basidiomycota, forms the subkingdom Dikarya. Its members are commonly known as the sac fungi or ascomycetes. It is the largest phylum of Fungi, with over 64,000 species. The def ...

(fungi that form their

spore In biology, a spore is a unit of sexual reproduction, sexual (in fungi) or asexual reproduction that may be adapted for biological dispersal, dispersal and for survival, often for extended periods of time, in unfavourable conditions. Spores fo ...

s in a sac-like

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 ...

) and is more or less synonymous with the slightly older invalid name Archiascomycetes (sometimes spelled Archaeascomycetes; archea = ancient). Recent molecular studies suggest that the group is monophyletic and basal to the rest of the Ascomycota. The major taxa are

Schizosaccharomycetes Schizosaccharomycetes is a class in the kingdom of fungi. It contains the order Schizosaccharomycetales, the fission yeasts. The genus Schizosaccharomyces is a broad and ancient clade within Ascomycota including five known fission yeast: ''Sch ...

Taphrinomycetes The Taphrinomycetes are a class of ascomycete fungi belonging to the subdivision Taphrinomycotina. It includes the single order Taphrinales, which includes 2 families, 8 genera and 140 species A species () is often defined as the largest ...

Neolectomycetes ''Neolecta'' is a genus of ascomycetous fungi. The species share the English designation "Earth tongues" along with some better-known fungi (e.g. '' Geoglossum'', '' Microglossum'') with a similar general form, but in fact they are only distantl ...

, and

Pneumocystis The Pneumocystidomycetes are a class of ascomycete fungi. It includes the single order Pneumocystidales, which contains the single monotypic family Pneumocystidaceae, which in turn contains the genus Genus (; : genera ) is a taxonomic rank ...

. The

are the

yeast Yeasts are eukaryotic, single-celled microorganisms classified as members of the fungus kingdom (biology), kingdom. The first yeast originated hundreds of millions of years ago, and at least 1,500 species are currently recognized. They are est ...

s (e.g. '' Schizosaccharomyces'') that reproduce by fission rather than budding, unlike most other yeasts, many of which are in the subdivision

Saccharomycotina Saccharomycotina is a subdivision (subphylum) of the division (phylum) Ascomycota in the kingdom Fungi. It comprises most of the ascomycete yeasts. The members of Saccharomycotina reproduce by budding and they do not produce ascocarps (fruiting ...

. The

are dimorphic plant parasites (e.g. '' Taphrina'') with both a yeast state and a filamentous ( hyphal) state in infected plants. They characteristically infect leaves, catkins, and branches, not roots. Taphrinomycetes form asci but no

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 ...

. The

are species in a single genus, '' Neolecta'', which are the only members of the subdivision that form

(fruiting bodies), and which specifically grow out of root tips. They may have a yeast state (ascospores bud in the asci). The Pneumocystidomycetes also encompasses only one genus of yeasts, ''Pneumocystis'', one of which causes ''Pneumocystis'' pneumonia in humans by developing cysts on the lung tissue. None has ascogenous hyphae giving rise to the asci.

References

The Oregon Coalition of Interdisciplinary Databases: "Archiascomycetes: Early Diverging Ascomycetes"
{{Taxonbar, from=Q133815 Ascomycota Opisthokont subphyla