| Reported in | Status | Registered by | ||
|---|---|---|---|---|
| Curtobacterium testaceum | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Curtobacterium saperdae | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Curtobacterium ginsengisoli | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Cupriavidus yeoncheonense | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Cupriavidus numazuensis | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Cupravidus yeoncheonense | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Cryobacterium mesophilum | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Cronobacter zurichensis | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Cronobacter pulveris | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Cronobacter helveticus | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Croceivirga thetidis | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Croceicoccus hydrothermalis | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Croceicoccus gelatinilyticus | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Croceicoccus estronivorus | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Croceibacterium xixiisoli | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Croceibacterium soli | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Croceibacterium salegens | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Croceibacterium atlanticum | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Cristispira | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Cristispira pectinis T | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Crenothrix | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Crenothrix polyspora T | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Crenotalea | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Crenotalea thermophila T | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Crassaminicella thermophila | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Crabtreella | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Crabtreella saccharophila T | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Coxiella burneti | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Cowdria | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Cowdria ruminantium T | Unknown | Valid (ICNP) | Excubia bot over 3 years ago |