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Fly with red parasites

Fly with red parasites
Middlesex County, New Jersey, USA
June 20, 2010
I found this fly struggling with three parasites (mites?) attached to its underside. Can anyone identify either the fly or its tormentors?

Moved from ID Request.

The mites are larval trombidioids.

... for the help with the parasites.

Thanks Ray!
Guilty of tormenting the fly or innocent ride-catchers?

Trombidioids (velvet mites... the group to which chiggers belong) are beautiful lumbering predators as adults, and parasitic as larvae. Most parasitize arthropods, like this syrphid, and once engorged will drop off and "pupate" into the predator stages.

How did you know the fly was a syrphid?

If you look at your cropped image, you can see the closed wing cells, but general gestalt is the best way. I don't know a whole lot of other flies that look anything like that with all closed wing cells, and that are attacked by trombidioids. For some reason, syrphids are very common hosts for velvet mites.

... for the explanation.

If possible, could you please crop this image so that the fly and hangers-on fill most of the frame? It will help our experts see the bugs a lot better... Thanks!

I'm not sure how much this will help.

It will help quite a bit - can see the wing venation on the fly much better in the cropped pic, for example. If you don't get a comment here soon, suggest moving to Diptera page for expert attention.

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