Domain Bacteria Woese et al. 1990
   Phylum Verrucomicrobia Garrity and Holt 2001 see Phylum Verrucomicrobia Hedlund 2011
     Class Verrucomicrobiae Hedlund et al. 1998
       Order Verrucomicrobiales Ward-Rainey et al. 1996
         Family Verrucomicrobiaceae Ward-Rainey et al. 1996
           Genus Prosthecobacter (ex Staley et al. 1976) Staley et al. 1980
           1 Genus Verrucomicrobium Schlesner 1988