USS Threadfin (SS-410), a , was the only vessel of the United States Navy to be named for the threadfin. Threadfin was laid down on 18 March 1944 at the Portsmouth Navy Yard in Kittery, Maine. She was launched on 26 June 1944 sponsored by Mrs. Frank G. Fox, and commissioned on 30 August 1944. Training and trials out of Portsmouth followed her final completion late in September. After transiting the Panama Canal in mid-November, the submarine reached Pearl Harbor early in December and conducted intensive training in preparation for her first war patrol. First war patrol Threadfin stood out of Pearl Harbor on 25 December. Early in January 1945, she reached her assigned patrol area in the waters just south of Kyūshū. There, she spent 30 of her 54 days at sea. She encountered numerous enemy aircraft, patrol craft, and fishing vessels, but only six targets worthy of a torpedo. On 30 January, Threadfin sighted a large enemy patrol craft, but prudently allowed her to pass unmolested in the hope of drawing a bead on any merchant vessels for which she might be running interference. Presently, a 2000-ton coastal freighter escorted by two patrol vessels and a plane crossed her path. Threadfin fired a spread of six torpedoes from a range of about . At least one of them struck home, obscuring the target in smoke and steam. The cargoman probably sank; but Threadfin could not verify that result visually because the escorts drove her deep with a persistent, though ineffective, depth charge attack. Two days later, the submarine encountered a Japanese . However, the enemy's course changes kept Threadfin from gaining an advantageous attack setup, and the Japanese "pig-boat" disappeared in the distance. Threadfin next happened upon two freighters escorted by three patrol craft. This time, the small convoy's position close inshore defied the American submarine's efforts to attack. The following day, she mistook another patrol vessel for a cargo ship and discovered her mistake in just enough time to make a deep dive to safety. That escapade also robbed her of a chance at a small convoy consisting of two small cargomen and two escorts. She sighted the convoy later when she returned to periscope depth; but, by then the ships had passed out of range. A week later, she launched six torpedoes at a minesweeper distant. In spite of an excellent fire-control solution, all six missed.