prokaryotes - bacteria see Domain Bacteria Woese et al. 1990
Status: extant
   Domain "Bacteria" Woese et al. 1990
  Status: extant
     Phylum "Proteobacteria" Garrity et al. 2005 see Superphylum Proteobacteria Craig et al. 2010
    Status: extant
       Class Epsilonproteobacteria Garrity et al. 2006
      Status: extant
         Order Campylobacterales Garrity et al. 2006
        Status: extant
           1 Family "Hydrogenimonaceae" Garrity et al. 2004 nom. nud. [monotypic]
          Status: extant
           2 Family Campylobacteraceae Vandamme and De Ley 1991
          Status: extant
           3 Family Helicobacteraceae Garrity et al. 2006
          Status: extant