Kingdom Protista (Haeckel, 1866) - protists Phylum Sarcomastigophora Honigberg & Balamuth, 1963 Subphylum Mastigophora Diesing, 1866 - flagellates Class Zoomastigophorea - "animal-like" flagellates see Phylum Zoomastigina Order Choanoflagellida Kent, 1880 - choanoflagellates see Class Choanoflagellatea Cavalier-Smith, 1998 Genus Monosiga Kent, 1880-1882