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 Terrabacteria Battistuzzi et al. 2004
               Phylum "Actinobacteria" Garrity and Holt 2001
                 Class Actinobacteriaᵀ Stackebrandt et al. 1997
                   Order Actinomycetalesᵀ Buchanan 1917 (Approved Lists 1980)
                     Suborder Corynebacterineae Stackebrandt et al. 1997
                       Family Nocardiaceae Castellani and Chalmers 1919 (Approved Lists 1980)
                         1.1 Genus Gordonia corrig. (ex Tsukamura 1971) Stackebrandt et al. 1989
                         1.2 Genus Skermania Chun et al. 1997 [monotypic]
                         1.3 Genus Millisia Soddell et al. 2006 [monotypic]
                         2.1.1 Genus Nocardiaᵀ Trevisan 1889 (Approved Lists 1980)
                         2.1.2 Genus Micropolyspora Lechevalier et al. 1961 (Approved Lists 1980) [monotypic]
                         2.2 Genus Rhodococcus Zopf 1891 (Approved Lists 1980)
                         2.3 Genus Smaragdicoccus Adachi et al. 2007 [monotypic]
                         3 Genus Williamsia Kämpfer et al. 1999