Caitian
The Caitians were a spacefaring feline humanoid species and long-standing members of the United Federation of Planets.

History 
Caitians were attending Starfleet Academy by the early 2250s, and the Caitian homeworld was a Federation member with members on the Federation Council by 2286. (; ) Caitians were present on Qualor II in 2381. ()

In the alternate reality, Caitians were present on Earth by 2259. ()

Biology 

The Caitians exhibited feline features, such as short faces, triangular ears, large eyes with vertically slitted s, whiskers, fangs, and a tail. Most were entirely covered with fur that could be orange, brown, gray, or black, and which could be solid, multicolored, or patterned. Some Caitians had four fingers (including a thumb) on each hand, while others had five. Additionally, the feet of some Caitians possessed a digitigrade configuration, while others had a plantigrade foot structure. There were also at least a few Caitians who had a very different, more Human-like appearance. (; ; ; )

When they needed to move quickly, Caitians could switch to quadrupedal locomotion, displaying feline agility and reaction times. They had sharp claws on their hands and feet, which led some to prefer going without footwear. Their claws could also be used to scale vertical surfaces, such as cliffs. (; )

The voices of some female Caitians had a soft purring quality. Agitated Caitians could also make a variety of cat-like hisses and yowls. (; )

Caitians experienced several hormonal cycles. One of these was the need to be intimate once a year, or else their hormones would drive them crazy; this could be alleviated using a libido post. Caitian females had coital hooks as part of their reproductive anatomy. When ed, Caitians enjoyed playing inside boxes. ()

Individuals
Named
M'Ress
T'Ana

Unnamed
Unnamed Caitians

Appendices

Appearances
A list of all appearances of Caitians (excluding the regular appearances of T'Ana):

Background information
The name of the species comes from , published by Lincoln Enterprises in , which claims that the Caitians are related to the Kzinti, and were from Cait. This is corroborated by extensive commentary by Larry Niven, author of most of the Known Space books and virtually the entire Known Space sub-series The Man-Kzin Wars, primarily found in his short story books "N-Space", "Playgrounds of the Mind", and "The Patchwork Man".

From StarTrek.com, "The felinoid Caitians and the warlike Kzinti share common roots in the deep past — as do Vulcans and Romulans. As with the Vulcans and the Romulans, the two groups went their separate ways to develop as two entirely different civilizations. The Caitians are fierce warriors when so called upon, but pride themselves on their accomplishments in arts and philosophy rather than on the martial arts. Natives of Cait tend to be small and sinewy; the females are as delicately dainty as the Siamese or Abyssinian cats of old Earth. Their family units are extremely close."

The Lincoln Enterprises biography of M'Ress similarly expanded on the Caitians, stating that they tended to be small and sinewy, with their females delicately dainty.

Damon Lindelof has confirmed that the alien twins  slept with in  were Caitians. 

According to Akiva Goldsman, Bjayzl from the  episode  was originally intended to be a Caitian.

Apocrypha 
The Caitians are expanded upon in FASA's Star Trek IV Sourcebook Update, which indicates that the feline humanoids seen in The Voyage Home were intended to be the same species.

The Last Unicorn and Decipher RPG books had to use the name "Regulans" because of copyright issues. 

M'Ress is also referred to as a Caitian in the audio story "Passage to Moauv".

Set in 2409, the computer game Star Trek Online features the Caitians as a playable species of the Federation faction, which also employs ships of unique Caitian design, e.g., the Atrox Carrier, Shikaris Escort, and Stalker Stealth Fighter. According to their description, Caitians are "known throughout their quadrant for their intelligence, curiosity, loyalty and love of beauty". The game includes several Caitian NPCs, including Enterprise-F Tactical Officer and Security Chief Lieutenant Kyona. It also depicts a species closely related to the Caitians called Ferasans.

External links

de:~/Spezies/TAS/1x06/1
ja:カイティアン
Species
Felines