| methanobrevibacter boviskoreani | species | | | species | 1348249 |
| methanobrevibacter ruminantium | species | archaea | bacteria | species | 83816 |
| methanobrevibacter smithii | species | archaea | bacteria | species | 2173 |
| methanobrevibacter sp. | no rank | archaea | bacteria | species | 66852 |
| methanobrevibacter woesei | species | archaea | bacteria | species | 190976 |