USS Proxima
From Star Trek: Theurgy Wiki
The USS Proxima was a 24th century Federation starship operated by Starfleet.
In the year 2373, the Proxima was on a exploration mission in the Gamma Quadrant when she disappeared. Involvement of the Dominion was suspected. (DS9 episode: "In Purgatory's Shadow"; Decipher RPG module: Starfleet Operations Manual)
(It is not been revealed what class of starship the USS Proxima was, but the Memory Beta website lists it as a Nebula class with the registry number of NCC-61952.)