C. Russo was the name of a Human Starfleet officer in the 22nd century.
In the 2150s, he was named as an Orbital Ergonomics officer on the dedication plaque of the NX-class starships. (ENT: "Broken Bow", dedication plaque; ENT: "Affliction", dedication plaque)
In January of 2155, he was named as a Payload Deploy officer on directory placards at the Fleet Operations Center, Sol Sector. His office was in room #1414. (ENT: "Demons", directories)