Phylum Ascomycota Caval.-Sm. (1998) - sac fungi Subphylum Taphrinomycotina O.E. Erikss. & Winka (1997) - basal ascomycetes 1 Class Archaeorhizomycetes Rosling & T.Y. James (2011) [monotypic] 2 Class Neolectomycetes O.E. Erikss. & Winka (1997) [monotypic] 3 Class Pneumocystidomycetes O.E. Erikss. & Winka (1997) [monotypic] 4 Class Schizosaccharomycetes O.E. Erikss. & Winka (1997) [monotypic] - fission yeasts 5 Class Taphrinomycetes O.E. Erikss. & Winka (1997) [monotypic]