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 Rhizobiales Kuykendall 2006 Family Hyphomicrobiaceae Babudieri 1950 (Approved Lists 1980) [Genus Microcyclus Ørskov 1928 (Approved Lists 1980) nom. illeg. [monotypic]] see Genus Ancylobacter Raj 1983 [Microcyclus aquaticusᵀ Ørskov 1928 (Approved Lists 1980) comb. illeg.] see Ancylobacter aquaticus (Ørskov 1928) Raj 1983