common green bottle fly

Common and widespread

3 or 4 generations. Early spring to late fall.

Warm moist climates; common around farms, slaughterhouses, and garbage cans.

This is a medium-sized blow fly. Adults are ⅜″ to ½″ long, slightly larger than a house fly.

The thorax is metallic bluish-green, gold, or both, with numerous short, black, bristle-like hairs (setae) and many longer bristles. Three grooves across the thorax delineate the three thoracic sections. The upper (dorsal) surface of the middle section has 3 bristles. A line bisecting the fly from front to rear would pass through these three bristles.

The abdomen is similar in color to the thorax.

The face is silvery. The eyes are red. The antennae are black. The mouthparts are yellowish.

The legs are black.

The wings are clear and have light brown veins.

Partially decomposed animal tissue in dead fish and other animals, dung, and garbage containing animal matter. Live sheep.

Males usually feed on flower nectar; females also feed on animal tissue

The female deposits a mass of up to 180 white or pale yellow eggs in carrion, dung, or garbage. Over the space of 3 weeks the female will lay a total of 2,000 to 3,000 eggs in 9 or 10 batches. The number and size of batches depends on the temperature. When the eggs hatch the maggots begin feeding on the material to which they are attached. They reach full size in 4 to 9 days, enter a pre-pupal stage, then burrow into the soil. In 7 to 115 days, depending on soil temperature, the adults emerge. Over the next 48 hours the body hardens and the wings become functional. Mating begins 3 to 8 days after emergence. Adults can travel many miles searching for carrion or another suitable breeding location.

In Minnesota there are 3 or 4 generations per year. The last generation overwinters in the soil as larva.

Sources: 7, 24, 29, 30.

Taxonomy
This species was formerly classified as Phaenicia sericata.

Forensics
This is often one of the first insects to visit a corpse, sometimes within minutes of death. Forensic scientists use the development of the larva of this species to determine the age of a corpse.

Maggot Therapy
Larvae are used on humans to painlessly remove dead or decaying tissue from wounds while leaving healthy tissue untouched and secreting a chemical that promotes tissue regeneration.