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]
           ?"viruses"
             Realm Riboviria
               Family Birnaviridae
                 1 Genus Aquabirnavirus
                 2 Genus Avibirnavirus [monotypic]
                 3 Genus Blosnavirus [monotypic]
                 4 Genus Entomobirnavirus [monotypic]