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Red wasp attacking black swallowtail caterpillar? - Trogus pennator

Red wasp attacking black swallowtail caterpillar? - Trogus pennator
Woodridge, Dupage County, Illinois, USA
July 23, 2010
A few bad, blurry shots of what I think may be a red wasp attacking a black swallowtail caterpillar. Sorry for the low quality, I was testing out a cheap (and bad) lens I just purchased when I saw this happening (the sad part is that I had a sharp 90mm macro in my bag, but no time to switch to it).

I suspect that the caterpillar's defensive reaction may have been too late. As for the pennator female sitting on the Queen Anne's lace, the late Ichneumoninae specialist, Gerd Heinrich (father of Bernd), used to collect Ichneumoninae on certain umbellifers, but he said that the best ones were the species found in the woods and that Queen Anne's lace wasn't very attractive for ichneumonids. However, in Europe, where Queen Anne's lace is native, ichneumonids apparently are common visitors to the flowers of the species.

Moved from ID Request.

Oh, wow!
This is actually a parasitic ichneumon, Trogus that is laying an egg in the caterpillar. The larva that hatches consumes the caterpillar from the inside out but still allows the caterpillar to pupate. An adult ichneumon will then emerge from the chrysalis. Great captures!

I suspected this might be some kind of cool parasite--I'm a bug dummy, but the way it crept up behind the caterpillar, rode it to the ground when it fell of the plant, then immediately left it to go sit on some queen anne's lace seemed pretty odd.

Another awful (this lens is hilariously soft) image of the bug

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