Natura - nature
   actualia - actual entities
     Mundus Plinius - physical world
       naturalia - natural bodies
         [[crown] organisms] see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
           [Phycobionta]
             [Division Pyrrhophyta Pascher (1914) [monotypic]]
               [Genus Bion H. Lohmann (1904)]
                 [†Bion perivelatum Eisenack (1937)] see Pterochitina perivelata (Eisenack, 1937)