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 Hypocreales Lindau (1897)
           Family Niessliaceae Kirschst. (1939)
             01 Genus Circioniesslia O.E. Erikss. (2006), orth. inval. see Genus Circinoniesslia Samuels & M.E.Barr (1998)
             02 Genus Cryptoniesslia Scheuer (1993)
             03 Genus Hyaloseta A.W.Ramaley (2001)
             04 Genus Malmeomyces Starbäck (1899)
             05 Genus Melanopsamma Niessl (1876)
             06 Genus Melchioria Penz. & Sacc. (1897)
             07 Genus Miyakeomyces Hara (1913)
             08 Genus Myrmaeciella Lindau (1897)
             09 Genus Niesslia Auersw. (1869)
             10 Genus Paraniesslia K.M. Tsui, K.D.Hyde & Hodgkiss (2001)
             11 Genus Pseudonectriella Petr. (1959)
             12 Genus Pseudorhynchia Höhn. (1909)
             13 Genus Taiwanascus Sivan. & H.S. Chang (1997)
             14 Genus Trichosphaerella E. Bommer, M. Rousseau & Sacc. (1891)
             15 Genus Valetoniella Höhn. (1909)
             16 Genus Valetoniellopsis Samuels & M.E.Barr (1998)