The Tirek VIII natives were a species of highly intelligent squid-like creatures native to Tirek VIII. They spent all of their lives in the ocean, and yet they had a tremendous civilization, one that existed for sixteen thousand years.
Benjamin Sisko used them as an example for Tork of the Hive that intelligent species such as theirs could exist on a planet. But Tork, hanging on to his people's views of planet dwellers, was skeptical of their intelligence. (DS9 novel: Objective: Bajor)