| Reported in | Status | Registered by | ||
|---|---|---|---|---|
| Arthrobacter ardleyensis | Unknown | Valid (ICNP) | Excubia bot about 3 years ago | |
| Arthrobacter antioxidans | Unknown | Valid (ICNP) | Excubia bot about 3 years ago | |
| Arthrobacter antarcticus | Unknown | Valid (ICNP) | Excubia bot about 3 years ago | |
| Arthrobacter albus | Unknown | Valid (ICNP) | Excubia bot about 3 years ago | |
| Arthrobacter albidus | Unknown | Valid (ICNP) | Excubia bot about 3 years ago | |
| Arsukibacterium tuosuense | Unknown | Valid (ICNP) | Excubia bot about 3 years ago | |
| Arsukibacterium perlucidum | Unknown | Valid (ICNP) | Excubia bot about 3 years ago | |
| Arsukibacterium indicum | Unknown | Valid (ICNP) | Excubia bot about 3 years ago | |
| Arsenophonus apicola | Unknown | Valid (ICNP) | Excubia bot about 3 years ago | |
| Arsenicicoccus cauae | Unknown | Valid (ICNP) | Excubia bot about 3 years ago | |
| Aristophania | Unknown | Valid (ICNP) | Excubia bot about 3 years ago | |
| Aristophania vespae T | Unknown | Valid (ICNP) | Excubia bot about 3 years ago | |
| Arcobacter vitoriensis | Unknown | Valid (ICNP) | Excubia bot about 3 years ago | |
| Arcobacter vandammei | Unknown | Valid (ICNP) | Excubia bot about 3 years ago | |
| Arcobacter parvus | Unknown | Valid (ICNP) | Excubia bot about 3 years ago | |
| Arcobacter lekithochrous | Unknown | Valid (ICNP) | Excubia bot about 3 years ago | |
| Arcobacter haliotis | Unknown | Valid (ICNP) | Excubia bot about 3 years ago | |
| Arcobacter arenosus | Unknown | Valid (ICNP) | Excubia bot about 3 years ago | |
| Arcobacter antarcticus | Unknown | Valid (ICNP) | Excubia bot about 3 years ago | |
| Archaeoglobus neptunius | Unknown | Valid (ICNP) | Excubia bot about 3 years ago | |
| Arcanobacterium pyogenes | Unknown | Valid (ICNP) | Excubia bot about 3 years ago | |
| Arcanobacterium buesumense | Unknown | Valid (ICNP) | Excubia bot about 3 years ago | |
| Arcanobacterium bonasi | Unknown | Valid (ICNP) | Excubia bot about 3 years ago | |
| Arcanobacterium bialowiezense | Unknown | Valid (ICNP) | Excubia bot about 3 years ago | |
| Arcanobacterium bernardiae | Unknown | Valid (ICNP) | Excubia bot about 3 years ago | |
| Arcanobacterium abortisuis | Unknown | Valid (ICNP) | Excubia bot about 3 years ago | |
| Arboriscoccus | Unknown | Valid (ICNP) | Excubia bot about 3 years ago | |
| Arboriscoccus pini T | Unknown | Valid (ICNP) | Excubia bot about 3 years ago | |
| Arachidicoccus terrestris | Unknown | Valid (ICNP) | Excubia bot about 3 years ago | |
| Aquisalinus |