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?] [Class Proteobacteria Stackebrandt et al. 1988] see Phylum Proteobacteria Garrity and Holt 2001 [Subclass "alpha"] see Class Alphaproteobacteria Garrity and Holt 2001 nom. nud. [Group 4] see Order Sphingomonadales