Ensign Ryson was a crewmember serving aboard the USS Voyager, under Captain Kathryn Janeway, when it was lost in the Delta Quadrant in 2371.
In 2375, Neelix had prepared a leg of Kelaran wildebeest for Ryson's birthday, however it ended up being the most recent "casualty" of the "Midnight Snacker", later identified as Seven of Nine. (VOY: "Infinite Regress")
This character was only mentioned in dialogue.