Kingdom Chlorobiota C.Jeffrey ex Doweld (2001) - plants see Subkingdom Viridiplantae Caval.-Sm. (1981)
   Subkingdom Bryobiotina Campb. (1890)
     Division Bryophyta A.Braun (1864) - mosses and liverworts see Phylum Bryophyta A.Braun (1864)
       Subdivision Bryophytina Engl. (1892) see Subphylum Bryophytina Engl. (1892)
         Class Bryopsida McClatchie (1897) - mosses
           Subclass Bryidae Engl. (1892) - mosses
             Superorder Hypnanae W.R.Buck & Goffinet ex W.R. Buck, C.J. Cox, A.J. Shaw & Goffinet (2005)
               Order Hypnales W.R. Buck & Vitt
                 Family Pterigynandraceae Schimp.
                   Genus Iwatsukiella W.R.Buck & H.A. Crum (1978)