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 Bifidobacteriales Stackebrandt et al. 1997 ?Genus Pelczaria Poston 1994 nom. rej.