Midges Flies and Mosquitoes: Diptera

Physical characteristics: Adult Mediterranean fruit flies measure 0.14 to 0.2 inches (3.5 to 5 millimeters) in length. The eyes are iridescent (IH-rih-DEH-sent), or shiny and multicolored. The wings are broad with yellow patterns. The females have a distinctive egg-laying tube, or ovipositor, on the tip of the abdomen. The larvae are white and narrow toward the head, becoming wider toward the rear. The tip of their abdomen is broad and flat. The dark reddish brown pupae are cylinder-shaped and about 0.12 inches (3 millimeters) in length.

Geographic range: This species is native to Africa. During the past one hundred years it has become established in countries in the Mediterranean region, including Spain, Italy, Greece, Jordan, Turkey, parts of Saudi Arabia, and most countries along the North African coast. It is also found in Portugal and the Hawaiian Islands. It is occasionally found in California and Florida in the continental United States, as well as in Mexico, Guatemala, and Chile.

The Mediterranean fruit fly is a major agricultural pest in temperate and subtropical regions worldwide. It attacks more than two hundred different kinds of fruit crops. (Illustration by Jonathan Higgins. Reproduced by permission.)

Habitat: The adult Mediterranean fruit flies are found wherever fruit trees grow. The larvae bore inside of fruit.

Diet: Larvae feed within the flesh of citrus, peach, and guava, among many other fruits. The adults sop up fruit juices, honeydew, and plant sap.

Behavior and reproduction: Adults fly only short distances, but winds may carry them up to several miles (kilometers) away.

Females lay one to ten eggs beneath the skin of ripening fruit. They may lay up to three hundred eggs in their lifetime. Eggs hatch after two or three days and molt twice within six to ten days. Mature larvae leave the fruit and burrow 1 to 2 inches (2.5 to 5 centimeters) into the soil to pupate. Adults emerge in about ten days. Males defend leaves on fruit trees as territories and release pheromones (FEH-re-moans), chemical scents attractive to females. Courtship includes brief wing flapping and head movements.

Mediterranean fruit flies and people: The Mediterranean fruit fly is a major agricultural pest in temperate and subtropical regions worldwide. It attacks over two hundred different kinds of fruit crops. Fly infestations in North, Central, and South America are eradicated by flooding the area with thousands of sterile males. Sterile males are exposed to low doses of radiation and cannot produce sperm. Although sterile, these males will still mate with females, but their eggs will not be fertilized.

Conservation status: This species is not considered endangered or threatened. ∎