4954 N. Shamrock Place, Tucson, AZ 85705

House Fly

Musca domestica

House Fly

Physical Features

Females are typically longer than males, but both sizes depend on the food available. On an average, they are 1/6 inch long. Females also have a broader space between their reddish eyes. Both have sponging mouthparts. The abdomen is gray or yellowish with dark markings, with males having a yellow underside. Body covered with fine hairs.

Life Cycle

Complete metamorphosis
This is a fast life cycle normally complete within 14 days if prime environmental conditions exist. Females deposit white egg clusters numbering about 75-150 eggs over a three-day period; resulting in a total of 500 eggs. The eggs are laid in moist, organic debris including manure and contents of trash cans. The white, legless larvae (commonly referred to as maggots) feed on the debris and can reach 3/8 inch in length over a 3-7 day period. The larva moves to a cooler area to pupate constructing a case from its last molting skin. After 3-4 days, a docile adult emerges. Normal activity begins in about 15 hours.


  • Diet: Moist organic debris
  • Activity: Constant activity in areas with proper environmental conditions
  • Preferred Climate: Warm to hot temperatures, 70 to 90 degrees
  • Defense: Size, speed, and leg hairs that excrete a sticky fluid so they can stick to ceilings and other hard to reach places.
  • Cautions: Equated with spreading bacterial diseases
  • Home Invasion: Flies will enter homes through any crack and crevice in search of food and egg laying sites.

Helpful Hints

  • Thorough sanitation practices around and in the home.
  • Recommend regular pest control service plan.



Nesting Sites

Areas of filth. Piles of garbage, animal feed or manure.