The Gentons were a civilization that fought the Gentonian trade wars some time ago. They were one of the races visited by a group of Ullians in the mid-24th century for their memory archive project.
A Genton contingent met with Jev and Tarmin for the telepathic memory retrieval project. (TNG: "Violations")
This species was only mentioned in dialogue.
According to Startrek.com
, the Gentons hailed from the planet
Genton (pronounced "JEN-tawn"). The web site dated the trade wars to a generation
or two before the 2360s