Ichneumon: Therion morio

Crane Fly? Damsel Fly? Really Off-Course Fly?
July 31, 2009
Hey there – Here’s a very interesting looking flying insect found yesterday, July 30th, at Massassauga Point Conservation Area, Prince Edward County, Ontario. Very sunny day, humid, temperatures around 28 Celsius. My wife works for the conservation authority and was in the field when she spotted it. I’ve done as much Internet searching as I can but cannot identify the insect. It was in a brushy, wooded area when the photo was taken, and when in flight its legs dangled much like a mud dobber, and it has orange antennae like a wood wasp, but it’s the tail end that has us stumped. It hovered much like a wasp when in flight.
Any help would be appreciated – thanks!
Glenn May-Anderson, Belleville, Ontario
Massassauga Point, Prince Edward County, Ontario

Male Megarhyssa atrata

Hi Glenn,
We receive many identification requests for female Giant Ichneumons in the genus Megarhyssa, but we receive very few images of the males.  This is a male Megarhyssa atrata.  The female has a three inch long ovipositor that is often mistaken for a stinger.  She uses her ovipositor to deposit eggs into dead and dying wood that is infested with wood boring larvae, the food for the larval Ichneumon.

Correction from Eric Eaton
August 4, 2009
Hi, Daniel:
… A couple other things:
The “Giant ichneumon:  male of the species” is incorrect.  The ichneumon in the image is not even in the same subfamily, and it is likely a female.
… Keep up the great job, Daniel:-)

Update:  Therion morio identified
August 19, 2013
We just received a new photo which we thought might be a male
Megarhyssa atrata, but our search for a matching photo led us to this old unidentified Ichneumon.  Searching BugGuide, we discovered it is Therion morio.

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