Leotiomyceta represents all the filamentous ascomycete fungi (

Pezizomycotina Pezizomycotina make up most of the Ascomycota fungi and include most lichenized fungi too. Pezizomycotina contains the filamentous ascomycetes and is a subdivision of the Ascomycota (fungi that form their spores in a sac-like ''ascus''). It is m ...

), excluding the classes Pezizomycetes and

Orbiliomycetes The Orbiliaceae are a family of saprobic sac fungi in the order Orbiliales. The family, first described by John Axel Nannfeldt in 1932, contains 288 species in 12 genera. Members of this family have a widespread distribution, but are more pr ...

. It is well supported in several studies comparing DNA sequences in

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

. It has originally been proposed as a superclass but later was proposed as a rankless

taxon In biology, a taxon ( back-formation from '' taxonomy''; plural taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular n ...

for any well supported group above class (together with saccharomyceta, dothideomyceta, and sordariomyceta). Rankless

taxa In biology, a taxon (back-formation from ''taxonomy''; plural taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular nam ...

do not strictly follow the rules for

taxonomic classification In biology, taxonomy () is the scientific study of naming, defining ( circumscribing) and classifying groups of biological organisms based on shared characteristics. Organisms are grouped into taxa (singular: taxon) and these groups are give ...

s in plants and fungi (

ICBN The ''International Code of Nomenclature for algae, fungi, and plants'' (ICN) is the set of rules and recommendations dealing with the formal botanical names that are given to plants, fungi and a few other groups of organisms, all those "trad ...

) and therefore these names are informal, although they appear to reflect natural groups.

References

Ascomycota Taxa described in 1997 Opisthokont unranked clades {{Ascomycota-stub