Kingdom Bacteria Cavalier-Smith 2002 - bacteria see Domain Bacteria Woese et al. 1990
   Subkingdom Unibacteria Cavalier-Smith 2002 see Domain Bacteria Woese et al. 1990
     Division Posibacteria Cavalier-Smith 2002
       Subdivision Actinobacteria Cavalier-Smith 2002 see Phylum Actinobacteria Garrity and Holt 2001
         Class Arthrobacteria Cavalier-Smith 2002 see Class Actinobacteria Stackebrandt et al. 1997