Kingdom [Animalia] Linnaeus, 1758 - animals
   Subkingdom Protozoa Goldfuss, 1818 see Kingdom Protozoa Goldfuss, 1818
     Class Flagellata see Subphylum Mastigophora Diesing, 1866
       Order Opalinina see Order Opalinida Poche, 1913
         1 Genus Protopalina Doflein, 1929 see Genus Protoopalina Metcalf, 1918
         2 Genus Zelleriella Metcalf, 1920, nom. nud.
         3 Genus Cepedea Metcalf, 1920
         4 Genus [Opalina] Purkinje & Valentin, 1835