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Photo#154681
Nephila spider with 3 small flies on her body
Copyright © 2007 Scott Camazine

Nephila spider with 3 small flies on her body
Near Baton Rouge, Louisiana, USA
October 15, 2007
Photographed this Nephila and noticed 3 small flies on the spider. Can anyone identify the flies? Are they parasitic? One of the flies has a distended abdomen. Is she filled with eggs?

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Nephila spider with 3 small flies on her body - Nephila clavipes Nephila spider with 3 small flies on her body
Contributed by Scott Camazine on 30 October, 2007 - 8:52pm
Last updated 2 November, 2007 - 4:09pm

Milichiidae flies.
The flies are of the family Milichiidae (geez, I can never remember how to spell that!), and they are habitually attracted to the prey of spiders, ambush bugs, and assassin bugs, especially if that prey exudes a defensive secretion (like stink bugs, coreids, etc). The flies here are either waiting for the spider's next meal, or are hanging out after dining on a prey item already discarded from the web....Please see more images in the guide under Milichiidae.
… Eric R. Eaton, 2 November, 2007 - 4:08pm

 
Milichiidae
The flies could be Paramyia nitens
… Irina Brake, 30 November, 2009 - 9:10am

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