Procaryotic Genera
   Domain "Bacteria" Woese et al. 1990
     Phylum Actinobacteria Garrity and Holt 2001 [monotypic]
       Class Actinobacteria Stackebrandt et al. 1997
         Subclass Actinobacteridae Stackebrandt et al. 1997 see Class Actinobacteria Stackebrandt et al. 1997
           1 Order Actinomycetales Buchanan 1917 (Approved Lists 1980)
           2 Order Bifidobacteriales Stackebrandt et al. 1997