More Urban Species: Flesh Fly

[urbpan]

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


You can see the checkerboard pattern on the abdomen in this photo.


Wash your hands afterward!

Comments

[deathling.livejournal.com]

Oh so thats probably whats always zooming around the ME's office.

[urbpan.livejournal.com]

Could well be. They're the BIG ones. They had them at the monkey place I volunteered, after a plumbing break meant no drainage for a little while.

[wirrrn.livejournal.com]

Ahh... the Forensic Entomologist's 'There is a Body here!" Red-Flag species...

[elainetyger.livejournal.com]

Thanks for this information -- I'll keep it in mind in case I run into one of those situations where no one can figure out where the flies in the basement or the rear storeroom are coming from.

In NY, virually any evidence of live rodents in a firm that makes, sells, or stores food is considered a critical deficiency. (Other jurisdictions might call that a major violation or simply Fail.) Flies, though, are only considered critical if they are in a food processing area and either they are landing on food or else management is not taking steps to keep them out and kill the ones that get in.

I can tell summer is coming because I found 3 critical deficiencies this week resulting from flies in the deli area of a grocery. All three places had the front door open, no fan in the deli area to blow the flies out of there, and no zapper or pest strips hanging anywhere.

[badnoodles.livejournal.com]

Sarcophagids are also interesting because they don't lay eggs. The fertilized eggs develop within the females' reproductive tracts, so that a first-stage larva can be deposited upon a piece of suitable carrion.

They are less useful than other cyclorraphan fly species for forensic work because they tend to come to a body rather later than the blowflies, and because they are virtually impossible to identify to species without a SEM. (The one exception being the fairly common Sarcophaga haemorrhoidalis, with it's bright orange butt).

I think they are quite pretty flies, if somewhat ungainly.

[urbpan.livejournal.com]

Ah! Combined with Badnoodles comment below, I have some good ideas now for rewriting this post. Thanks :)

[urbpan.livejournal.com]

Now that first point is a real interesting fact that I should have included. Also the second point is good. I'm going to have to rewrite this one if I want to include it in my imagined 365 urban species book. (Probably I should find a S. haemorroidalis, so that I can have it identified to species).

[badnoodles.livejournal.com]

Nah, you can do it like the professionals and go with "Sarcophaga spp." It's easy, it's lazy, it's fun!

flesh flies

[(Anonymous)]

I Had a problem with rats about 6 months ago. We put poison around and found 6 dead ones. There was a smell and I was seeing flesh flies. I haven't seen any flies in about 6 months. The smell went away. Yesterday I started seeing the flies again. Always by the back window. The most I saw was about 10 or 12. I would kill one and then I would see another one. Can anyone help me. There is no smell and the poison that I left out for the rats have not been touched. Can anyone suggest something or tell me if they will go away on there own.

Re: flesh flies

[urbpan.livejournal.com]

I suspect they'll dwindle over time, but in the meanwhile I'd suggest hanging fly tape by that window. That should do it.

flies in my office

[(Anonymous)]

hi! guys i have been having a very rough time since a dead rat was in my office.it was behind a concealed furniture i had to get a carpenter to get access to that space.I am in India, [Bombay].some how after 4-5 days i got rid of the smell by ventilating the office.and trying to vacuum the location of the dead rat.never found the rat but saw some marks and hairy stuff on the wall that is concealed.had to use a torch.and connected the vacuum hose to flexible pipe & inserted in the unreachable area.finally got rid of the smell.but after a week i saw these huge flesh flies in the office all over about 50 of them just hanging on the furniture.i killed and got rid of them but after an hour or so saw 10-12 of them again. hanging on the blinds.after observing them closely identified them as flesh flies.as earlier i had accessed the net to find out the type of fly invasion i had.can someone advice me here of what is going on at my work place.and yes i killed the rest of the flies too.but wher thry coming from and why?

Re: flies in my office

[urbpan.livejournal.com]

There could be another dead rat somewhere, or maybe enough material left from the old one to attract the flies. Alternately, wherever the rat was running it was sure to have left droppings behind. House or bottle flies could have laid eggs in that which would have attracted the flesh flies.

Thanks!

[(Anonymous)]

I am interested in Forensic Entomology and Found your article quite interesting and helpful. Do need a key though of Dipteran larva. Can anyone help me out?

[(Anonymous)]

we currently have these in a house we are renting right now in Louisiana. we moved in about 3 months ago. there are about 30-40 of them in our master bathroom. they seem to have become present over the past 24 hours. we did notice a foul odor in our house a few weeks ago. how long does it take for the flies to mature and become present? how do we get rid of them?

[urbpan.livejournal.com]

They mature in 10 days or less. I'd hang some fly tape or a scented fly trap to catch the adults in the bathroom.

Seriously buggin' out

[(Anonymous)]

My house has had flesh flies for two days. I thought it was from the trash can outside with soiled diapers from two babies! I plan on cleaning bin on friday when trash is picked up. They are on the windows in the rooms where our dog is this morning. I killed all flies last night, only to wake up to 30 to 40 this morning. Can they be on or in my dog? He does have an ongoing ear infection? That drops help on and off. I don't see anything on my labrador. Please help...When to call exterminator!

[(Anonymous)]

30 to 40 was an understatement. I just killed 70! I put there remains outside in the trash bin. There are no flies outside. Please please help. Will they go away on there own? Dog is on the porch as a control. I don't think its her. Im giving her a bath in a bit. My house is clean and no odor anywhere.

[(Anonymous)]

30 to 40 was an understatement. I just killed 70! I put there remains outside in the trash bin. There are no flies outside. Please please help. Will they go away on there own? Dog is on the porch as a control. I don't think its her. Im giving her a bath in a bit. My house is clean and no odor anywhere.

Re: Seriously buggin' out

[urbpan.livejournal.com]

The flies are almost certainly coming from something dead in your walls or under your house or in the attic or something like that. Your dog would be showing other symptoms (extreme pain, death) if he had 30 flies emerging from him per day.

Re: Seriously buggin' out

[(Anonymous)]

Thank You! We bombed house and they are gone. The temp also dropped 20 degrees the following days. Thanks again