prokaryotes - bacteria see Domain Bacteria Woese et al. 1990
   Domain "Bacteria" Woese et al. 1990
     Phylum "Proteobacteria" Garrity et al. 2005 see Superphylum Proteobacteria Craig et al. 2010
       Class Gammaproteobacteria Garrity et al. 2005
         Order Thiotrichales Garrity et al. 2005
           1 Family Francisellaceae Sjöstedt 2005 [monotypic]
           2 Family Piscirickettsiaceae Fryer and Lannan 2005
           3 Family Thiotrichaceae Garrity et al. 2005
           4 Genus Caedibacter (ex Preer et al. 1974) Preer and Preer 1982, incertae sedis
           5 Genus Fangia Lau et al. 2007, incertae sedis