A blow fly, Calliphora sp. (Diptera: Calliphoridae). Photo by Drees.
Common Name: Blow fly
Scientific Name: Calliphora sp.
Order: Diptera
Description: Include a number of species including the common bluebottle fly, Calliphora vomitoria (Linnaeus) the green bottlefly, Phaenicia sericata (Meigen) and others. Adult flies are metallic blue, green, copper or black colored flies that otherwise resemble house flies in appearance. The hair on the terminal antennal segment (arista) is feathery (plumose).
Other Calliphoridae include the black blow fly, Phormia regina (Meigen), and the cluster fly, Pollenia rudis (Fabricius). Larvae of cluster flies parasitize earth worms. Adult flies hibernate in homes. Species of the family, Sarcophagidae, are also found in association with carrion and excrement, although some feed on decaying vegetation or are parasitic. One example of this family is the flesh fly, Sarcophaga haemorrhoidalis Fallen (Diptera: Sarcophagidae). Adults are similar to blow flies but are patterned a checkerboard (tessellated) of gray and black on the abdomen. The hair on the last antennal segment (arista) is bear or less feathery than those of Calliphoridae.
Life Cycle: Female flies lay eggs on or near suitable habitats. Tiny maggots hatch from eggs in 6 to 48 hours. Maggots develop through three stages (instars) on carrion for 3 to 9 days before leaving the food source to pupate in soil. After 2 to 7 days in a prepupal stage, they form a puparium from their last larval stage skin. A fourth larval stage occurs within the puparium before pupation. Adult flies emerge 10 to 17 days after the formation of the puparium. Development from egg to adult occurs in 16 to 35 days, depending on temperature and environmental conditions.
Habitat and Food Source(s): Maggots have hook-like mouthparts that tease apart tissues in which they live. Adults have sponge-like mouthparts similar to those of house flies. Larvae (maggots) primarily feed on dead animals and animal refuge. Some feed on vegetation and others are obligatory parasites. These flies are attracted to any type of fresh meat or road kill left in the field.
Pest Status: Similar to houseflies when common indoors; larvae feed on dead animals or garbage waste; some species are parasitic.
For additional information, contact your local Texas A&M AgriLife Extension Service agent or search for other state Extension offices.
Literature: Ebling 1978; James & Harwood 1969.