Phylum Ascomycota Caval.-Sm. (1998) - sac fungi Subphylum Taphrinomycotina O.E. Erikss. & Winka (1997) - basal ascomycetes Class Pneumocystidomycetes O.E. Erikss. & Winka (1997) [monotypic] Order Pneumocystidales O.E. Erikss. (1994) [monotypic] Family Pneumocystidaceae O.E. Erikss. (1994) [monotypic] 1 Genus Pneumocystis P. Delanoë & Delanoë (1912)