A hard-pressed Caatati commander who takes Voyager's ejected warp core and demands supplies and Seven of Nine in exchange for it.
Lumas commands one of the ragged ships carrying survivors of the Caatati, whose civilisation was destroyed by the Borg. He appears in the fourth-season Voyager episode Day of Honor.
After Voyager gives aid to another group of Caatati, Lumas arrives asking for more than Janeway can afford. When the ship is later forced to eject its warp core, his people tow it away, then return in force to demand thorium, food and the former drone, on whom they want revenge.
Seven of Nine offers a way out: Borg knowledge of how to make the isotopes that the Caatati need to run their ships. Lumas accepts the device and hands back the core.