Bigyra Cavalier-Smith, 1998
   Subphylum Opalozoa Cavalier-Smith, 1992
     Infraphylum Placidozoa Cavalier-Smith, 2013
       Superclass Wobblata Cavalier-Smith, 2013 [paraphyletic]
         Class Nanomonadea Cavalier-Smith, 2013 [monotypic]
           Order Uniciliatida Cavalier-Smith, 2013
             Family Solenicolidae Cavalier-Smith, 2013 [monotypic]
               1 Genus Solenicola Pavillard, 1916