prokaryotes - bacteria see Domain Bacteria Woese et al. 1990 stat. inval.
   Domain "Bacteria" Woese et al. 1990 stat. inval. see Domain Bacteria Woese et al. 2024
     Phylum "Proteobacteria" Garrity et al. 2005 stat. inval. see Phylum Pseudomonadota Garrity et al. 2021
       Class Gammaproteobacteria Garrity et al. 2005
         Order Legionellales Garrity et al. 2005
           1 Family Coxiellaceae Garrity et al. 2005
           2 Family Legionellaceae Brenner et al. 1979 (Approved Lists 1980)
           3 Genus Rickettsiella Philip 1956 (Approved Lists 1980), incertae sedis