Natura - nature
   actualia - actual entities
     Mundus Plinius - physical world
       naturalia - natural bodies
         [crown] Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
           Clade neomura Cavalier-Smith, 1987
             Domain Eukaryota Chatton, 1925 - eukaryotes
               "protists" incertae sedis
                 Group †Acritarcha Evitt, 1963, incertae sedis [polyphyletic] - acritarchs
                   Genus †Baltisphaeridium Eisenack, 1958 ex Eisenack, 1959
                     †Baltisphaeridium longispinosumᵀ (Eisenack, 1931)
                       †Baltisphaeridium longispinosum f. filiferaᵀ Eisenack (1959)