[viruses]
   Realm Riboviria
     Order Nidovirales
       Suborder Tornidovirineae [monotypic]
         Family Tobaniviridae
           Subfamily Serpentovirinae
             Genus Pregotovirus [monotypic]
               Subgenus Roypretovirus [monotypic]
                 Ball python nidovirus 1ᵀ