PhylumMethanobacteriota
| Taxon: | Rank: |
| Aciduliprofundum | genus |
| Archaeoglobi | class |
| Halobacteria | class |
| Methanobacteria | class |
| Methanococci | class |
| Methanomicrobia | class |
| Methanonatronarchaeia | class |
| Methanopyri | class |
| Methanosarcinia | class |
| Thermococci | class |
| Thermoplasmata | class |