Keiran MacDuff was a Satarran operative (September 27, 2334-February 17, 2368) disguised as a human. Posing as a Starfleet Commander, with the duties of first officer, aboard USS Enterprise-D. With the crew suffering from temporary amnesia, and forged intel on the ship's computers, MacDuff was assigned with directing the vessel command staff to start an armed conflict between his race and the Lysians. His cover was exposed as well as his true purpose. His "parents", from the Gamma Canaris system were Joseph and Les MacDuff. (TNG episode: "Conundrum")
MacDuff's date of birth is from the fake bio, seen on the display screen. Date of death is from the original televison airdate.