[organisms] see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
   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 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