Eukaryota Chatton, 1925 - eukaryotes see Domain Eukaryota Chatton, 1925 Phylum Alveolata Cavalier-Smith, 1991 see Superphylum Alveolata Cavalier-Smith, 1991 Subphylum Ciliophora Doflein, 1901 see Phylum Ciliophora Doflein, 1901 Class Spirotrichea Bütschli, 1889 Subclass Heterotrichia (Stein, 1859) Cavalier-Smith, 1993