Concise hierarchy

(Kingdom) Methanobacteriati - (Phylum) Methanobacteriota - (Class) Methanomicrobia

Subsequent positions

Methanococci (Class) Boone 2001 nom. inval.		Ref: D.R. Boone, 2001: 246. [assumed]
Methanomicrobia (Class) Garrity et al. 2005 nom. inval.		Ref: G.M. Garrity et al., 2005: 167, App. 2 (p. 207).

Current position

Methanomicrobia (Class) Garrity et al. 2005 nom. inval.

Ref: LPSN, 2020-present: [20 Nov 2025]; LPSN[20 Nov 2025].

Alternative positions

Euryarchaeota (Kingdom) Woese et al. 1990
Methanococci (Class) Boone 2001 nom. inval.	Ref: D.R. Boone, 2001: 246. [new position]
Methanothermea (Class) Cavalier-Smith 2002 nom. rej.	Ref: T. Cavalier-Smith, 2002a: tbl. 1 (p. 14). [new position]

Historical positions

Methanomicrobia (Class) Garrity et al. 2005 nom. inval.	Ref: J.P. Euzéby, 2016: [31 Aug 2017].
Methanomicrobia (Class) Garrity et al. 2005 nom. inval.	Ref: M.A. Ruggiero et al., 2015b: table 2 (p. 2).
Methanomicrobia (Class) Garrity et al. 2005 nom. inval.	Ref: G.M. Garrity et al., 2007: 15.
Methanothermea (Class) Cavalier-Smith 2002 nom. rej.	Ref: T. Cavalier-Smith, 2002a: tbl. 1 (p. 14). [new position]
Methanococci (Class) Boone 2001 nom. inval.	Ref: G.M. Garrity et al., 2001b: 2. [new position]
Methanococci (Class) Boone 2001 nom. inval.	Ref: D.R. Boone, 2001: 246; xiv. [new position]
Methanococci (Class) Boone 2001 nom. inval.	Ref: G.M. Garrity & J.G. Holt, 2001a: [156]. [new position]

Number of Subtaxa

2026	Available in Systema Naturae 2000	5f;17g;44s
1989-present	Systema Naturae 2000: 20 Nov 2025	[5f;17g]
2016	J.P. Euzéby: [6 Sep 2017]	[4f;12g]
2007	G.M. Garrity et al.	[3f;9g;30s]
2001b	G.M. Garrity et al.: 2	[3f;9g]
2001	D.R. Boone	[3f;9g]
2001a	G.M. Garrity & J.G. Holt: [156]	[3f;9g]
2000		3f9g