Currently viewing the category: "Ichneumons"
What's That Bug? does not endorse extermination

Subject: Please can you tell me what this is?
Location: Dalby forest. England
August 13, 2016 8:50 am
Saw this in the summer in north east England in a dense forest.
Signature: Perplexed

Sabre Wasp

Sabre Wasp

Dear Perplexed,
This is a parasitoid Ichneumon, the Sabre Wasp,
Rhyssa persuasoria, in the act of ovipositing, and you can verify our identification on Bio Images.  According to Bug Life:  “Wood drillers Ichneumons often locate their host species by ‘smelling’ them and this is exactly what Sabre Wasps do. Female Sabre Wasps locate the wood-boring larvae of the huge and beautiful Horntail Wasp (Uroceris gigas) by using their antennae to detect scents that emanate from the larvae’s wooden tunnels.  When a female Sabre Wasp has located a promising site, she starts tapping on the surface of the wood with her antennae. She then uses her long egg-laying tail to drill a ‘probe’ hole. She may drill a few probe holes before deciding on an appropriate position, and then drills as deep as she can. After 30-60 minutes, if successful, she will breach the tunnel wall, sting the larvae and then lay an egg on its body. With the larvae paralysed by the sting, it awaits the inevitable demise of being consumed alive by the Sabre Wasp grub.”  Your image is gorgeous, and though we have many similar looking images of North American relatives called Stump Stabbers in the act of ovipositing, your image is the first European example we have of your Sabre Wasp in the act of laying eggs.

What's That Bug? does not endorse extermination

Subject: Cool looking
Location: Michigan
August 11, 2016 4:29 pm
What is this thing in n michigan
Signature: John Peters

Giant Ichneumon

Giant Ichneumon

Dear John,
This is a Giant Ichneumon in the genus
Megarhyssa, most likely Megarhyssa macrurus.  It appears to be drinking from a water fountain.  Please confirm that.  Giant Ichneumons are sometimes called Stump Stabbers because the female uses her long ovipositor to lay eggs that will hatch into larvae that feed on the wood boring larvae of Horntails like the Pigeon Horntail.

What's That Bug? does not endorse extermination

Subject: Weird bug
Location: Denver
July 21, 2016 6:06 pm
Just in the ya4d collecting japanese beetles when we saw a very weird bug.
Signature: LouAnn

Therion morio

Therion morio

Dear LouAnn,
This amazing looking parasitoid Ichneumon,
Therion morio, does not have a common name. According to BugGuide:  “Host: moth larvae, including Hyphantria cunea (Fall Webworm).”  The female in your images is probably searching for caterpillars upon which to lay an egg so that her young can feed on the living caterpillar, eventually killing it.

Therion morio

Therion morio

What's That Bug? does not endorse extermination

Subject: Red mystery wasp
Location: near Ottawa, Ontario
July 18, 2016 3:43 pm
What is this beautiful little insect? I’m guessing some sort of wasp, maybe a parasitic wasp? I photographed it last week along Cedar Grove Nature Trail near Ottawa, where I see many fascinating tiny insects I can’t identify!
Signature: Suzanne

Ichneumon Stalks Caterpillar

Ichneumon Stalks Caterpillar

Dear Suzanne,
This is an amazing image.  We suspect that the Ichneumon Wasp, which you speculated correctly is a parasitoid, is stalking the Caterpillar.  Caterpillars are a common host to many species of Ichneumons.  Ichneumons are often very host specific, frequently limiting their prey to a single genus, or even a single species.  We are probably not even going to attempt to identify this Ichneumon beyond the family level as according to BugGuide, there are:  “About 5,000 described species in North America, possibly 3,000 more undescribed”  The caterpillar may be an Inchworm in the family Geometridae.

What's That Bug? does not endorse extermination

Subject: Giant Wood Wasp??? Or not
Location: Northern Ontario
July 16, 2016 11:44 am
Real curious about the attached bug.
Found it flying they an open wooded area.
Was thinking it might be a Giant Wood Wasp but the long (5-6″)tail made us think otherwise.
Signature: Regards, Teshaun

Stump Stabber

Stump Stabber

Dear Teshaun,
This is a Giant Ichnuemon, Megarhyssa atrata, commonly called a Stump Stabber, and anyone who has ever watched a female Stump Stabber laying eggs might be fooled into thinking it is a Wood Wasp.  Wood Wasps, including the Pigeon Horntail, oviposit or lay eggs on dead and dying trees and the larvae are wood borers.  The Stump Stabber is a parasitoid whose larvae feed on the larvae of Pigeon Horntails.

What's That Bug? does not endorse extermination

Subject: Unknown bug
Location: NorthWest Ontario
June 27, 2016 8:14 pm
This tree fell down in a recent storm and is known as a Manitoba Maple. This photo is taken of two of the several black yellow winged dragonfly scorpion like taled flyer. Behaviour of which is interesting and peculiar caught the eyes of many… They appeared to be mating or birthing or fertilizing… Hard to say if the tentacles at the end of their tales were their own or coming out…or if the green thick fluid like stuff was a placenta or mating fluids or ? Very bizarre as they seemed to be labouring if not pleasuring. One I thought was birthing actually burrowed it’s once widened tail tip into a hole in the bark made by termites….nestled it there and rested. A couple of these bugs looked rather fresh, young, and of the brighter yellow and reddish brown, one somewhat curled up and drying off …I wondered if was born recently. A couple of the bugs were blacker than others, almost all black and their tails so black you would hardly notice them in the shadows of the tree pieces or against the earth.
I live in northwestern Ontario bordering with Manitoba. We just had a lot of rain, 44mm this past weekend.
What is this bug
Signature: Curious C

Two Giant Ichneumons Oviposit

Two Giant Ichneumons Oviposit

Dear Curious C,
In your image, you have captured two different species of female Giant Ichneumons in the genus
Megarhyssa, sometimes called Stump Stabbers, and each is in the process of laying eggs or ovipositing.  Giant Ichneumons are parasitoid wasps and their host insects are the wood boring larvae of Wood Wasps in the subfamily Tremecinae, including the Pigeon Horntail, that feed on the wood of deciduous trees.  The smaller brown and yellow individual is Megarhyssa macrurus, and the larger, black and yellow individual is Megarhyssa atrata.

Wow! Very informative and fast ID’ing!! Thankyou so much!!:)
Curious C 😉

What's That Bug? does not endorse extermination