| Reported in | Status | Registered by | ||
|---|---|---|---|---|
| Mesoflavibacter aestuarii | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Mesobacterium | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Mesobacterium pallidum T | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Mergibacter | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Mergibacter septicus T | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Merdimmobilis | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Merdimmobilis hominis T | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Membranihabitans | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Membranihabitans marinus T | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Melittangium alboraceum | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Melitea | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Melitea salexigens T | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Melissococcus pluton | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Melisococcus | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Melisococcus plutonius | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Melisococcus plutonis T | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Melaminivora suipulveris | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Meiothermus timidus | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Meiothermus terrae | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Meiothermus roseus | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Meiothermus chliarophilus | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Megasphaera hominis | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Megasphaera butyrica | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Meganema | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Meganema perideroedes T | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Megamonas hypermegas | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Megalodesulfovibrio gigas T | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Mediterraneibacter hominis | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Mediannikoviicoccus | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Mediannikoviicoccus vaginalis T | Unknown | Valid (ICNP) | Excubia bot over 3 years ago |