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"
             Order Ortervirales
               Family Retroviridae
                 Subfamily Orthoretrovirinae
                   Genus Epsilonretrovirus
                     1 Walleye dermal sarcoma virusᵀ
                     2.1 Walleye epidermal hyperplasia virus 1
                     2.2 Walleye epidermal hyperplasia virus 2