Phylum Ascomycota Caval.-Sm. (1998) - sac fungi Class Pneumocystidomycetes O.E. Erikss. & Winka (1997) Order Pneumocystidales O.E. Erikss. (1994) Family Pneumocystidaceae O.E. Erikss. (1994) Genus Pneumocystis P. Delanoë & Delanoë (1912)