Fruit fly, this small, red-eyed fly breeds rapidly in decaying vegetables, fermenting fruit, beer, wine, vinegar or cider.
Improperly rinsed mops, cloths etc., used to clean up kitchen floors, may also act as breeding sites.
Eggs, larvae and pupae are all found in the decaying medium. The life cycle can be completed it 7 days under ideal conditions.
Fruit processing plants, fruit markets and wineries are often seriously infested with these flies when spilled liquid has not been cleaned up.