Which group of sisters did Phineus need help from the Argonauts to deal with, known as the "hounds of Zeus"?

Phineus sought the help of the Argonauts to deal with the Harpies, known as the "hounds of Zeus." In mythology, the Harpies are described as winged spirits, often depicted as carrying away individuals or stealing food, particularly from Phineus, a seer who was punished by the gods. The Harpies were sent as a divine retribution for his offenses, specifically blinding him. The Argonauts intervened to free Phineus from the torment caused by the Harpies by driving them away, which allowed him to regain his dignity and ensure that his prophecies could be fulfilled without their interference. This significance of the Harpies as agents of punishment and their connection to divine retribution distinguishes them from the other groups mentioned. The Furies are associated with vengeance, the Sirens are known for their alluring songs, and Nymphs are nature spirits, each having their distinct characteristics that do not align with the circumstances Phineus faced with the Harpies.