Chelon

The Rigellians were a sentient race. 

They were descended from a race of saber-toothed turtles who learned to walk upright. They ranged in height from about 1.75 meters to 2 meters or more.

Rigellians had attendants who served, fed, and cared for them. This gave the attendants the real power in Rigellian society. They only had one gender and reproduced by laying eggs.

When worn, armor served a mainly ceremonial function.
 * Details about this species, including their name, comes from notes created by Fred Phillips and Robert Fletcher for Star Trek: The Motion Picture and can be found in The Making of Star Trek The Motion Picture 

Apocrypha
In some novels these Rigellians are presumed to come from the same solar system - Rigel - as the Rigelians; their specific species being "Chelon," or "Rigellian Chelon." When Mego produced a 3.75" Saurian action figure for its ST:TMP line, the company inadvertently called it a "Rigellian". In the Last Unicorn Games and Decipher role-playing games, they are called "Chelarians" and hail from Rigel III (Chelar).