[organisms] see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
   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 Chromatiales Imhoff 2005
           Family Halothiobacillaceae Kelly and Wood 2005
             Genus Halothiobacillus Kelly and Wood 2000
               1 Halothiobacillus neapolitanus (Parker 1957) Kelly and Wood 2000
               2 Halothiobacillus halophilus (Wood and Kelly 1995) Kelly and Wood 2000
               3 Halothiobacillus hydrothermalis (Durand et al. 1997) Kelly and Wood 2000
               4 Halothiobacillus kellyi Sievert et al. 2000