USS Harlequin (AM-365) was an Admirable-class minesweeper built for the United States Navy during World War II.

Harlequin was launched 3 June 1944 by Willamette Iron and Steel Works, Portland, Oregon; sponsored by Mrs. Mary M. Doig, whose husband and son were reported missing in action and who also had another son, a brother, and nine nephews in the Navy.

Reporting to San Pedro, California, for shakedown 19 October, Harlequin remained there until 29 November, when she sailed south, reaching New Orleans, Louisiana, 15 December.

From 1976–1978 she was disarmed and converted to an oceanographic research vessel; she was renamed ARM Oceanográfico (H02) around this same time.

Some time after April 1999, she was rearmed and converted to a school ship (Spanish: barque escuela) and renamed ARM Aldabaran (BE02).