Xelatian

The Xelatians are a sapient, spacefaring species from Xelata, the third planet of the Tau 56 system. Their homeworld became a member of the United Federation of Planets at some point in or prior to 2286.

Biology
Xelatians are an aquatic cephalopod-like species with four-meter-long tentacles in place of arms and legs. Their language is a combination of bioluminescent pigments and telepathy. When meeting with land-based species, they wear water-filled environmental suits and their faces are concealed by masks to protect them from the bright light.

Appearances

 * Star Trek IV: The Voyage Home (1986)