Ascomycota - Modern Classification of Ascomycota

Modern Classification of Ascomycota

There are three subphyla that are described and accepted:

• The Pezizomycotina are the largest subphylum and contains all ascomycetes that produce ascocarps (fruiting bodies), except for one genus, Neolecta, in the Taphrinomycotina. It is roughly equivalent to the previous taxon, Euascomycetes. The Pezizomycotina includes most macroscopic "ascos" such as truffles, ergot, ascolichens, cup fungi (discomycetes), pyrenomycetes, lorchels, and caterpillar fungus. It also contains microscopic fungi such as powdery mildews, dermatophytic fungi, and Laboulbeniales.
• The Saccharomycotina comprise most of the "true" yeasts, such as baker's yeast and Candida, which are single-celled (unicellular) fungi, which reproduce vegetatively by budding. Most of these species were previously classified in a taxon called Hemiascomycetes.
• The Taphrinomycotina include a disparate and basal group within the Ascomycota that was recognized following molecular (DNA) analyses. The taxon was originally named Archiascomycetes (or Archaeascomycetes). It includes both hyphal fungi (Neolecta, Taphrina, Archaeorhizomyces), fission yeasts (Schizosaccharomyces), and the mammalian lung parasite, Pneumocystis.

Ribosomal RNA gene sequencing of soil suggests that there may be a fourth subphylum of Ascomycota (termed Soil Clone Group I or SCGI), that has not been described in cultures or based on fruiting bodies. SCGI organisms are only known from DNA sequences found in soils worldwide and are placed between the Taphriomycotina and the Saccharomycotina.