Bigyra Cavalier-Smith, 1998
   Subphylum Opalozoa Cavalier-Smith, 1992
     Infraphylum Bikosia Cavalier-Smith, 2013 [monotypic]
       Class Bikosea Cavalier-Smith, 2013
         1 Subclass Bicosidia Cavalier-Smith, 2006
         2 Subclass Rictidia Cavalier-Smith, 2013 [monotypic]