Rigellian (Star Trek)

The Rigellians are a spacefaring chelonianoid species native to Rigel V and a member race of the United Federation of Planets. They are a mono-gendered oviparous species evolved from saber-toothed ancestors. Their bodies are covered in reptilian scales. They have clawed fingers, large orange beaks and full black eyes. Despite their chelonianoid nature, modern Rigellians no longer have shells. Their individual size varies widely, with the smaller ones acting as the ruling class and the larger ones as egg carriers for the former. Their blood chemistry is similar to that of Vulcans, likely indicating that they too use copper to carry oxygen molecules in the blood as do many Earth animals (such as many arthropods and mollusks). They are also vulnerable to a neurological disease known as Tuvan Syndrome, which also affects Romulans.

Behind the scenes
The Rigellians appeared unnamed in Star Trek: The Motion Picture, their only canonical appearance so far, but have been mentioned in multiple Star Trek series. The information on their biology and evolution comes from designer Robert Fletcher.

In Star Trek, the Rigel system is also home to a savage humanoid species known as the Kalar from Rigel VII, making it possible that the information about Rigellian blood being similar to Vulcans (from "Journey to Babel") and/or their being susceptible to the Romulan disease (as mentioned in Deep Space Nine) might actually refer to the Kalar. Apparently human characters in the episodes "Shore Leave" and "Wolf in the Fold" have been identified as native to Rigel II and Rigel IV respectively, indicating that there are human colonies on these worlds. Rigel X, as seen on Star Trek: Enterprise, is inhabited by an extremely diverse multi-species community. Rigel XII is a scarcely-inhabited mining colony, as seen in "Mudd's Women".

To make matters more complicated, a humanoid species seen on later Star Trek: Enterprise has been identified as Rigellians, despite the fact that they look very dissimilar to the chelonian creatures from The Motion Picture. It is possible that these represent an immigrant species which was misidentified as native Rigellians in the 22nd century and the system was later reclaimed by the chelonians, but this is just speculation. It is also possible that they represent a different native Rigellian species, or even a different ethnic group or caste which belongs to the same species as the reptilian Rigellians. However, Dr. Phlox once mentioned the Rigellians as a species with four or five genders, contradicting Fletcher's claim that Rigellians are mono-gendered, and therefore strongly suggesting that Enterprise ' s Rigellians are not the same species as this one.

In non-canonical media, the Rigellians are referred to as the Chelons, from Rigel III. According to the Star Trek expanded universe, there are six native species to the Rigel system: the Chelons or Chelarians from Rigel III, the human-like Rigelians (Kalar warriors) from Rigel VII, the Enterprise Rigelians, a race of Vulcanoids from Rigel V (the ones referred to in "Journey to Babel"), a rat-like species from Rigel IV, and a silver-skinned humanoid species also from Rigel IV.

The Saurian action figure produced by Mego was incorrectly marketed as a Rigellian.