Adults may be dull yellowish, brownish yellow, or brownish black in color and range from 1/10 to 1/5-inch long. Most species have red eyes. Larvae are very small (ranging from 1/10 to 1/5-inch-long), dirty white, and maggot-shaped. They can be recognized by the stalked posterior spiracles on the last abdominal segment.
Fruit flies are small pests that are commonly found in homes, restaurants and other facilities where food is processed. They are found on moist, decaying matter that has been stationary for several days.
Fruit flies feed on decaying matter, especially fruits and vegetables. Fruit flies are found in unsanitary conditions, so they are a potential heath concern especially when present in health facilities.
Female fruit flies lay their eggs on the surface of rotting fruits and vegetables. Each female may lay as many as 500 eggs. These eggs hatch into larvae which molt twice before becoming fully grown. The larvae feed on the yeast organisms and fungi growing in infested material, and through their feeding efforts, they soon turn their food into a semi-liquid “mess.” When the full-grown larvae are ready to pupate, they leave the food material for dryer area. Complete development from egg to adult under summer conditions may be completed in 8 to 10 days. Mating takes place soon after adult emergence, usually within a few hours and egg laying begins about 24 hours later.
Common areas for infestations include drains in sinks and floor drains in commercial places, as well as under appliances that tend to have residual moisture. Food can also accumulate in cracks, and under broken floor tiles, and attract fruit flies once they begin to break down. Cleaning is the first step in an effective plan for control, as well as eliminating moisture. Depending on the location this may not always be practical, but it is an important step in overall, long term control. Clean interiors of drains with special kits designed to easily access a floor drain and clean under appliances and other stationery objects.