Procaryotic Genera Domain "Bacteria" Woese et al. 1990 Phylum Proteobacteria Garrity and Holt 2001 see Phylum Proteobacteria Garrity et al. 2005 Class "Deltaproteobacteria" Garrity et al. 2001 nom. ined. see Class Deltaproteobacteria Kuever et al. 2006 Order "Syntrophobacterales" see Order Syntrophobacterales Kuever et al. 2006 Family "Syntrophaceae" see Family Syntrophaceae Kuever et al. 2006 Genus Smithella Liu et al. 1999