Official Canon Edit
Felinids are a race of abhumans from the planet of Carlos McConnell. This is the full extent of canon information about them.
TTS Canon Edit
In TTS, a group of Guardsmen make contact with the planet, with several of them excited to "see some catlady action," believing the Felinids to be a race of catgirls. When the Felinids' diplomat arrives, the guardsmen look on in horror, as it is a housecat with a human head and speaking in creepy, halting voice similar to that of a cat attempting to speak human language.