| Reported in | Status | Registered by | ||
|---|---|---|---|---|
| Zarconia | ||||
| Zarconia navalis T | ||||
| Zafaria | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Zafaria cholistanensis T | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Yuhushiella | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Yuhushiella deserti T | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Youxingia | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Youxingia wuxianensis T | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Yoonia ponticola | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Yoonia acticola | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Yersinia rochesterensis | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Yersinia pseudotuberculosis subsp. pseudotuberculosis | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Yersinia pseudotuberculosis subsp. pestis | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Yersinia philomiragia | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Yersinia occitanica | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Yersinia kristensenii subsp. rochesterensis | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Yaniella fodinae | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Yania | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Yania halotolerans T | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Yania flava | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Yangia | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Yangia pacifica T | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Yangia mangrovi | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Xylanimicrobium | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Xylanimicrobium pachnodae T | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Xylanibacterium | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Xylanibacterium ulmi T | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Xylanibacter ruminicola | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Xylanibacter rodentium | Unknown | Valid (ICNP) | Excubia bot over 3 years ago | |
| Xylanibacter rarus | Unknown | Valid (ICNP) | Excubia bot over 3 years ago |