urbpan | More Urban Species: Flesh Fly (Reply)

Flesh fly, Sarcophaga sp.

There are a surprising number of species of flies associated with urban life. Moist refuse provides nursery space for the adorable babies of houseflies, bottle flies, and others. But the abundance of squirming maggots in fragrant muck is sure to attract predators. Surprisingly, one of these is the larva of the flesh fly.

There are quite a few species of flesh fly, virtually identical in appearance to our eyes: usually a bit bigger than a house fly, with three stripes on the thorax and a checkerboard on the abdomen. Northern climes may have 30 species in the genus Sarcophaga, while there may be hundreds in warmer, wetter places. Long noticed at carcasses and corpses, the fly's scientific name means 'flesh eater,' but in fact their maggots are flesh eater eaters. Still, forensic entomologists can use the appearance of Sarcophaga maggots as an aid to determine time of death.

I should hasten to add, the genus is a diverse one, and in addition to maggot predators, it includes species that develop as parasites on insects, earthworms or slugs, those that are coprophages, and one whose maggots live only on lizard eggs. Flesh flies found indoors are most often seen in the wake of a poison-based rodent control program. Poisoned mice die in the walls of a building whereupon their carcasses are eaten by 'filth fly' maggots, which are preyed on by flesh fly maggots. (Later the skin and fur are eaten by a host of dermestid beetles and clothes moths and other detritivores.) Flesh flies are important predators and decomposers but they are potential carriers of disease, and certainly the appearance of a great many of them in an urban environment shouldn't be ignored. Like many insects we find distasteful, flesh flies may be a sign that something somewhere is quite rotten.

Further reading for flesh fly fans.

http://www.zmuc.dk/entoweb/sarcoweb/sarcweb/biology/Srcphgna/Bio_Sarc.htm
Biology of the Sarcophaginae

http://www.springerlink.com/content/q3x37636233q204p/
Pilot study on synanthropic flies (e.g. Musca, Sarcophaga, Calliphora, Fannia, Lucilia, Stomoxys) as vectors of pathogenic microorganisms

http://www.icb.usp.br/~marcelcp/Sarcophaga.htm
The Veterinary Parasitology Images Gallery, University of São Paulo, Sarcophaga sp.

http://www.bioimages.org.uk/html/T2704.HTM
BioImages: The Virtual Field-Guide (UK), Sarcophaga (a genus of flesh flies)

journals.tubitak.gov.tr/havuz/zoo-0706-11.pdf
Contributions to the Knowledge of Flesh Flies (Diptera: Sarcophagidae) from Turkey, with a New Record