Kingdom Fungi R.T.Moore (1980) - fungi
   Subkingdom Dikarya Hibbett, T.Y. James & Vilgalys (2007)
     Phylum Ascomycota Caval.-Sm. (1998) - sac fungi
       Subphylum Pezizomycotina O.E. Erikss. & Winka (1997)
         Class Sordariomycetes O.E. Erikss. & Winka (1997)
           Subclass Hypocreomycetidae O.E. Erikss. & Winka (1997)
             Order Microascales Luttr. ex Benny & Kimbr. (1980)
               Genus Petriella Curzi (1930)