[organisms] see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
   Domain Bacteria Woese et al. 1990
     Phylum "Actinobacteria" Garrity and Holt 2001
       Class "Actinobacteria" Stackebrandt et al. 1997
         Subclass Actinobacteridae Stackebrandt et al. 1997 see Class Actinobacteria Stackebrandt et al. 1997
           Order Actinomycetales Buchanan 1917 (Approved Lists 1980)
             Suborder Corynebacterineae Stackebrandt et al. 1997
               Family "Williamsiaceae" see Family Nocardiaceae Castellani and Chalmers 1919 (Approved Lists 1980)
                 Genus Williamsia Kämpfer et al. 1999
                   1 Williamsia muralis Kämpfer et al. 1999
                   2 Williamsia deligens Yassin and Hupfer 2006
                   3 Williamsia marianensis Pathom-aree et al. 2006
                   4 Williamsia maris Stach et al. 2004