A species known only from a lunchtime debate between Garak and Bashir in 2370, concerning a Trelonian general who had his own brother executed as a traitor.
The Trelonians are a species mentioned in the Deep Space Nine episode Profit and Loss and never seen on screen.
Over lunch, Garak and Bashir argue about the case of the Trelonian General Yiri, who had his brother put to death for treason against the Trelonian government. Bashir protests that the evidence against the man was merely circumstantial. Garak takes the opposite view and admires a man prepared to put the state before his family.
The exchange is typical of the pair's lunches, in which Garak tests Bashir's Federation ideals against a Cardassian sense of duty. It also foreshadows the episode's plot, in which Garak must decide what to do about Cardassian dissidents who have taken refuge on the station.