| Description | Species | First Mention |
| Intelligent race plagued by insatiable hunger | |
| Parasitic species that inhabit the brains of others | |
| Extinct crab-like broccoli farmers | |
| Peaceful vegetarian race enslaved by the Yeerks | |
| Galactic chess player. Proponent of chaos and destruction | |
| Inhabit the bodies of canines | |
| Creators of the Hork Bajir | |
| Nearly-omnipotent meddler with a non-interference policy | |
| Extinct species which survivies only in sub-zero temperatures | |
| Ant-like race from the cretaceous period | |