Phylum Radiolaria Müller, 1858 see Subphylum Radiozoa Cavalier-Smith, 1987 Superclass Polycystina Ehrenberg, 1838 see Superclass Polycystinia Ehrenberg, 1838 Class Sphaerellaria Haeckel, 1881 Order Sphaerellata Haeckel, 1887 Family Xiphostylidae Haeckel, 1881 Subfamily Stylosphaerinae Haeckel, 1881 Genus †Protoxiphotractus Pessagno, 1973