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] Domain Bacteria Woese et al. 1990 [paraphyletic?] Superphylum "Proteobacteria" Craig et al. 2010 Phylum "Zetaproteobacteria" Emerson et al., 2007 [monotypic] 1 Class "Zetaproteobacteria"ᵀ Emerson et al. 2007 [monotypic]