Giant Ichneumon

What is this?
August 11, 2009
I saw this critter in North East Ohio. It was boring into a tree with its 4 or 5 inch tail…the body was maybe 2 to 3 inches long. What the heck is it?
North Eastern Ohio

Giant Ichneumon ovipositing
Giant Ichneumon ovipositing

Hi Kenny,
You have spotted a Giant Ichneumon, Megarhyssa macrurus, in the process of ovipositing.  Giant Ichneumons are parasitoids whose larvae feed on the wood boring larvae of the Pigeon Horntail and other Wood Wasps.  The female Giant Ichneumon locates a wood boring larva and then uses her lengthy ovipositor to deposit her egg in the proximity of the wood boring larva.
You can find more information on BugGuide.

1 thought on “Giant Ichneumon”

  1. I have seen a female of these in my front yard a few times this summer. I was able to get a picture of it today. Thanks for posting what it is! I was somewhat correct as to my assessment for what it was. I thought it looked like a hornet-meets-dragonfly. Haha


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