 "Portunus" was laid down as "LST-330" by the Philadelphia Naval Shipyard, 12 November 1942; launched 11 February 1943 as "Portunus" (AGP-4); and commissioned at Baltimore, Maryland, 12 June 1943, Lt. Comdr.James R. Hanna in command.After shakedown along the U.S. East Coast, this motor torpedo boat tender departed the U.S. 23 July 1943 in task group TG 29.6 for the Panama Canal, whence she continued to Australia.