Bigyra Cavalier-Smith, 1998
   Subphylum Opalozoa Cavalier-Smith, 1992
     Infraphylum Bikosia Cavalier-Smith, 2013 [monotypic]
       Class Bikosea Cavalier-Smith, 2013
         Subclass Bicosidia Cavalier-Smith, 2006
           Superorder Cyathobodoniae Cavalier-Smith, 1993
             Order Pseudodendromonadida Hibberd, 1985
               1 Family Pseudodendromonadidae Patterson & Zölffel, 1991
               2 Family Siluaniidae Karpov, 1998
               3 Family Paramonadidae Cavalier-Smith, 2006 [monotypic]
               4 Family Nanidae Cavalier-Smith, 2013 [monotypic]
               5 Family Neradidae Cavalier-Smith, 2006 [monotypic]
               6 Family Filidae Cavalier-Smith, 2013 [monotypic]