Phylum Ascomycota Caval.-Sm. (1998) - sac fungi
   Subphylum Pezizomycotina O.E. Erikss. & Winka (1997)
     Class Sordariomycetes O.E. Erikss. & Winka (1997)
       Order Spathulosporales Kohlm. (1973), incertae sedis
         Family Spathulosporaceae Kohlm. (1973)
           1 Genus Retrostium Nakagiri & Tad. Ito (1997)
           2 Genus Spathulospora A.R. Caval. & T.W. Johnson (1965)