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 Picobirnaviridae [monotypic] Genus Picobirnavirusᵀ 1 Human picobirnavirusᵀ 2 Rabbit picobirnavirus