(written from a Production point of view)
James W. Jansen (born 27 July 1945; age 76), sometimes credited as Jim Jansen, first appeared as Faren Kag in the Star Trek: Deep Space Nine first season episode "The Storyteller" and Lucsly in the fifth season episode "Trials and Tribble-ations".
Interestingly, his character's name in "Trials and Tribble-ations" is an anagram of Scully's from The X-Files. Jansen appeared in the pilot episode of that series as Dr. Heitz Werber and reprised the role five years later in the episodes "Patient X" and "The Red and the Black".
In 2011, Jansen made a guest appearance on the NBC series Parks and Recreation, whose regular cast includes Adam Scott.