The Legarans are a species native to the Alpha Quadrant world of Legara IV. The species lives in pools of thick liquids that are maintained at a temperature of 150° C and dislike bright areas. They are noted for their strict observance of protocol. (TNG episode: "Sarek")
Legaran bodies turn orange after death. For this reason, display of the color orange is considered a grave offense. The use of furnishings and decorations are also considered taboo.
Ambassador Sarek of Vulcan began a dialog with the race in the 2270s. By the 2290s he was confident that his relationship with them would bear fruit, but felt that the Federation would have to be patient with the Legarans. (TOS novel: The Fearful Summons)
The Legarans were invited to observe initial diplomatic talks between the Federation and the Cardassian Union in 2327. These talks turned out to be a Cardassian ploy to sabotage Ambassador Sarek's negotiations with the Legarans. (TOS comic: "Enter the Wolves")
By 2366, final negotiations were scheduled between Sarek and the Legarans aboard the USS Enterprise orbiting Legara IV, prior to the signing of a treaty with the Federation. The conference was almost cancelled when it was revealed that Sarek was suffering from Bendii Syndrome, as the Legarans would not accept a new negotiator. The conference was able to go forward when Sarek performed a mind meld with Captain Jean-Luc Picard, thus gaining Picard's emotional control long enough to conclude the talks and, after ninety-three years, sign the treaty. (TNG episode: "Sarek")