This article lists the orders of the Bacteria. The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LPSN) and National Center for Biotechnology Information (NCBI) and the phylogeny is based on 16S rRNA-based LTP release 132 by The All-Species Living Tree Project.
Phylogeny
National Center for Biotechnology Information (NCBI) taxonomy was initially used to decorate the genome tree via tax2tree. The 16S rRNA-based Greengenes taxonomy is used to supplement the taxonomy particularly in regions of the tree with no cultured representatives. List of Prokaryotic names with Standing in Nomenclature (LPSN) is used as the primary taxonomic authority for establishing naming priorities. Taxonomic ranks are normalised using phylorank and the taxonomy manually curated to remove polyphyletic groups.
Cladogram was taken from GTDB release 08-RS214 (28 April 2023).
Clade Terrabacteria
Phylum Chloroflexota
Class "Bathosphaeria" Mehrshad et al. 2018
?"Bathosphaerales" Mehrshad et al. 2018 [DTDB tag: JG30-KF-CM66]
Class ?"Poriflexia" Kogawa et al. 2022
Class "Umbricyclopia" Mehrshad et al. 2018
?"Umbricyclopales" Mehrshad et al. 2018 (TK10) Class "Limnocylindria" Mehrshad et al. 2018 "Limnocylindrales" Mehrshad et al. 2018 (SL56) Class Ktedobacteria corrig. Cavaletti et al. 2007 Ktedobacterales corrig. Cavaletti et al. 2007 (Thermogemmatisporales) Class Dehalococcoidia Löffler et al. 2013 Dehalococcoidales Löffler et al. 2013 Tepidiformales Kochetkova et al. 2020 Class "Caldilineia" Oren, Parte & Garrity 2016 ex Cavalier-Smith 2020 Aggregatilineales Nakahara et al. 2019 ("Phototrophicales") Anaerolineales Yamada et al. 2006 Ardenticatenales Kawaichi et al. 2013 Caldilineales Yamada et al. 2006 "Roseilineaceae" Ward et al. 2021 { J036} "Promineifilales" corrig. Thermoflexales Dodsworth et al. 2014 Class Chloroflexia Gupta et al. 2013 Chloroflexales Gupta et al. 2013 (Herpetosiphonales, Kallotenuales) "Thermobaculales" Thermomicrobiales Garrity & Holt 2002 (Sphaerobacterales)
Phylum Dormibacteraeota
Class "Dormibacteria" (sic) Montgomery et al. 2021 (AD3) ?"Aeolococcales" Montgomery et al. 2021 "Dormibacterales" (sic) Montgomery et al. 2021
Phylum Armatimonadota
Class Abditibacteriia Tahon et al. 2018 (FBP) Abditibacteriales Tahon et al. 2018 Class HRBIN17 "Candidatus Fervidibacter" Rinke et al. 2013 { HRBIN17: HRBIN17} (OctSpa1-106) Class UBA5829 "Candidatus Hippobium" Gilroy et al. 2022 { UBA5829: UBA5829} Class Fimbriimonadia Im et al. 2012 Fimbriimonadales Im et al. 2012 Class Chthonomonadia Oren, Parte & Garrity 2016 Chthonomonadales Lee et al. 2011 Class Armatimonadia Tamaki et al. 2011 (OP10) Armatimonadales Tamaki et al. 2011 Capsulimonadales Li, Kudo & Tonouchi 2018
Phylum Eremiobacterota
Class "Eudoremicrobiia" Paoli et al. 2022
?"Eudoremicrobiales" Paoli et al. 2022
Class "Xenobia" Ji et al. 2021 (UBP9) "Xenobiales" Ji et al. 2021 Class "Eremiobacteriia" corrig. Ward, Cardona & Holland-Moritz 2019 (WPS2) "Baltobacterales" Ward, Cardona & Holland-Moritz 2019 "Eremiobacterales" Ward, Cardona & Holland-Moritz 2019
Clade Firmicutes
Firmicutes incertae sedis
Class Desulfitisporia Sorokin & Merkel 2023
Desulfitisporales Sorokin & Merkel 2023
Class Fermentithermobacillia Kadnikov et al. 2023
Fermentithermobacillales Kadnikov et al. 2023
Class Thermolithobacteria Sokolova et al. 2007
Thermolithobacterales Sokolova et al. 2007
Phylum Bacillota E
Class UBA3575
"Candidatus Acetocimmeria" Smith et al. 2021 { UBA3575: UBA3575}
Class "Sulfobacillia" "Sulfobacillales" Cavalier-Smith 2020 Class "Symbiobacteriia" Wang et al. 2021 "Symbiobacteriales" Class "Thermaerobacteria" "Thermaerobacterales"
Phylum Bacillota G
Class Limnochordia Watanabe, Kojima & Fukui 2015
Limnochordales Watanabe, Kojima & Fukui 2015
Class "Hydrogenisporia" Pallen, Rodriguez-R & Alikhan 2022
"Capillibacteriales" Pallen, Rodriguez-R & Alikhan 2022 [UBA10575]
"Hydrogenisporales" Pallen, Rodriguez-R & Alikhan 2022 [UBA8346]
Phylum "Halanaerobiaeota"
Class "Halanaerobiia" Cavalier-Smith 2020
"Anoxybacterales" Pallen, Rodriguez-R & Alikhan 2022 { DY22613}
Halanaerobiales corrig. Rainey & Zhilina 1995
"Halobacteroidales"