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Photo Information
Copyright: Yves Grenier (eev) Gold Star Critiquer/Silver Workshop Editor/Gold Note Writer [C: 64 W: 33 N: 66] (756)
Genre: Animals
Medium: Color
Date Taken: 2008-09-23
Categories: Insects
Camera: Canon 30 D, Sigma 105mm F/2.8 EX 100 Macro
Exposure: f/7.1, 1/160 seconds
More Photo Info: [view]
Photo Version: Final Version, Original Version
Date Submitted: 2008-10-08 6:23
Viewed: 4672
Points: 4
[Note Guidelines] Photographer's Note
I have reposted this shot for a few of reasons. First the orientation of the shot was inaccurate. Secondly I wanted to zoom in more closely to the subject. Finally, I now have a better idea of what type of wasp I was dealing with. This is a saber wasp or Rhyssa persuasoria. The scientific name means 'persuasive burglar'.

This is a parasitic species widely found in North America, Europe and Asia. They inhabit clearings, tracks and footpaths in coniferous forest; precisely where I found this female laying her eggs beneath the bark of a giant pine.

They have slender bodies, with a wasp waist, and long, flexible antennae. The apparently fearsome-looking sting at the end of the female wasp's abdomen is actually an ovipositor (egg-laying instrument). This is protected within a sheath. This species has a black body with pale yellow/white markings on the abdominal segments. The legs are orange.

Ichneumons are parasites that lay their eggs in or on the larvae of other insects or spiders. The HOSTS of giant ichneumons are usually the larvae of horntails, or wood wasps, and related species, as well as the larvae of longhorn beetles. The female looks for hosts, which live within the timber. She may detect them through the smell of their droppings, which are then contaminated by fungi, or by sensing their vibrations within the wood. However she does it, the accuracy with which she locates them is remarkable. When she finds the right spot, she drives her slender ovipositor into the wood (which is what you are witnessing in this picture) by rotating the two halves backwards and forwards very rapidly. She lays one egg next to or on the host larvae. The whole process takes about 20-40 minutes.

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Hi Yves:

You have caugth a very nice moment of this Ichneumonid. I have tried to take some photos of this kind of insects , but is so difficult to achieve very detailed and sharp image of so thin and dark insects. Tfs.


  • Great 
  • batu Gold Star Critiquer/Gold Star Workshop Editor/Gold Note Writer [C: 1079 W: 293 N: 4497] (16383)
  • [2008-10-08 9:25]

Hello Yves,
such a superb picture of the wasp in this particular pocsure is not expected from the thumbnail.
It's a real surprise. The point of view is well selected and you achieved excellent sharpness.
Depth of field yould be a bit broader so that the ovipositor is included. f/10 was possible, I think!
Best wishes, Peter

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