Charlie Russo was a Starfleet officer in the 24th century.
In 2353, he was listed as a Starfleet Operational Support Services officer on a directory placard in Starbase 32, Maxia sector. His room number was #75260. (TNG: "Violations", directory)
In 2373, he was listed as a Tactical Ops officer on the dedication plaque of the USS Prometheus. (VOY: "Message in a Bottle", dedication plaque)
This character was only mentioned in writing.