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 "Alphaproteobacteria" Garrity et al., 2006 [monotypic] Class Alphaproteobacteriaᵀ Garrity et al. 2006 Order Sphingomonadales Yabuuchi and Kosako 2006 Family Erythrobacteraceae Lee et al. 2005 Genus Porphyrobacter Fuerst et al. 1993 Porphyrobacter sanguineus (ex Ahrens and Rheinheimer 1968) Hiraishi et al. 2002