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 Rhodospirillales Pfennig and Trüper 1971 (Approved Lists 1980) Family Rhodospirillaceae Pfennig and Trüper 1971 (Approved Lists 1980) Genus Skermanella Sly and Stackebrandt 1999 Skermanella parooensisᵀ (Skerman et al. 1983) Sly and Stackebrandt 1999