Calderobacterium Kryukov et al. 1984 Calderobacterium hydrogenophilum Kryukov et al. 1984 Universal Root Woese et al. 1990 Bacteria (None 2015) Woese et al. 1990 Aquificota corrig. Reysenbach 2021 Aquificae (sic) Reysenbach 2021 non Aquificae Reysenbach 2002 Aquificae Reysenbach 2002 emend. Gupta and Lali 2013 non Aquificae Reysenbach 2021 Aquificales Reysenbach 2002 emend. Gupta and Lali 2013 Aquificaceae Reysenbach 2002 emend. Gupta and Lali 2013 Calderobacterium Kryukov et al. 1984 Aquificaceae Reysenbach 2002 emend. Gupta and Lali 2013 Hydrogenobaculum Stöhr et al. 2001 Thermocrinis Huber et al. 1999 Hydrogenobacter Kawasumi et al. 1984 Hydrogenivirga Nakagawa et al. 2004 Aquifex Huber et al. 1992 Calderobacterium hydrogenophilum Kryukov et al. 1984 Kryukov V.R. Savelyeva N.D. Pusheva M.A. Calderobacterium hydrogenophilum nov. gen., nov. sp., an extreme thermophilic bacterium and its hydrogenase activity. 1983 52 781 788 Mikrobiologiya (Russian) 0026-3656