Phylum Ascomycota Caval.-Sm. (1998) - sac fungi
   Subphylum Pezizomycotina O.E. Erikss. & Winka (1997)
     Class Sordariomycetes O.E. Erikss. & Winka (1997)
       Subclass Diaporthomycetidae Senan., Maharachch. & K.D.Hyde (2015)
         Order Diaporthales Nannf. (1932)
           Family Sydowiellaceae Lar.N. Vassiljeva (1987)
             01 Genus Alborbis Senan. & K.D.Hyde (2017)
             02 Genus Breviappendix Senan. & K.D.Hyde (2017)
             03 Genus Cainiella E. Müll. (1957)
             04 Genus Calosporella J.Schröt. (1897)
             05 Genus Chapeckia M.E.Barr (1978)
             06 Genus Hapalocystis Auersw. ex Fuckel (1863)
             07 Genus Italiomyces Senan., Camporesi & K.D.Hyde (2017)
             08 Genus Lambro Racib. (1900)
             09 Genus Paragnomonia Senan. & K.D.Hyde (2017)
             10 Genus Ranulospora Senan., Camporesi & K.D.Hyde (2017)
             11 Genus Rossmania Lar.N. Vassiljeva (2001)
             12 Genus Sillia P.Karst. (1873)
             13 Genus Sydowiella Petr. (1923)
             14 Genus Tenuiappendicula Senan., Camporesi & K.D.Hyde (2017)
             15 Genus Tortilispora Senan. & K.D.Hyde (2017)