Antedean

Antedeans are a race of fish-like humanoids native to planet Antede III.

Circa 2345, the USS Lexington hosted a diplomatic conference with the Antedeans, with Ambassador Curzon Dax representing the Federation. (novel: The Brave and the Bold)

In 2365, the USS Enterprise-D transported two Antedean dignitaries from Antede III to a conference on Pacifica. They were, however, revealed to be assassins by Betazoid Ambassador Lwaxana Troi. (TNG episode: "Manhunt")