USS Marpessa (SP-787)

USS Marpessa (SP-787) was a United States Navy patrol vessel in commission from 1917 to 1919.

Marpessa was built in 1916 as a private, twin-engine wooden motorboat of the same name by the Mathis Yacht Building Company at Camden, New Jersey. On 18 August 1917, the U.S. Navy acquired her from her owner, W. J. Matheson of Camden, for use as a section patrol boat during World War I. She was enrolled in the Naval Coast Defense Reserve on 8 September 1917 and commissioned as USS Marpessa (SP-787) on 1 October 1917 with Ensign H. W. Mathewson, USNRF, in command.

Assigned to the 7th Naval District and based at Marathon, Florida, Marpessa patrolled the southern Atlantic coast of Florida for the rest of World War I.

Marpessa was returned to Matheson on 7 January 1919.