L. Castro was a Human Starfleet officer in the 22nd century.
In 2151, she was listed as a Propulsion Systems officer on the dedication plaque of the Enterprise NX-01. (ENT: "Broken Bow", dedication plaque).
In January of 2155, she was listed as a Payloads officer on directory placards at Starfleet Command's Fleet Operations Center, Sol Sector. His office was located in room #4244. (ENT: "Demons", directories)