Tuesday, September 18, 2007


I've wanted to get a photo of one of these ALL summer. They are amazing looking insects when adult, and on the hunt.

Long and evil-looking, a black (or dark) body and bright orange (when adult) legs, with a huge ovipositor at the rear.
They do not sit still for long though - always twitching, moving quickly and flying far too quickly for me to get a decent shot.

This is the Ichneumon wasp, of which there are many species in the UK. I think this species is Pimpla hypochondriaca.

I've seen them on and off all summer, but never seen one sit still. Until now.
Unfortunately for me, this individual is probably the most dowdy example I've seen. Very often the legs of this Ichneumon are very bright orange - this one has dull orange legs.
Never mind. I managed to sneak up on her before the sun had warmed her up sufficiently to move off.

Most ichneumons are endoparasites of Lepidopteral pupae, or to put it a different way, they parasitise the inside (endo) of moth and butterfly pupae, or grubs.
The very long ovipositor( no thicker than a human hair really) is inserted needle-like often through the bark of a tree, into the pupa, and the eggs are laid inside the victim.
Just to make sure everything goes to plan, the female ichneumon also injects venom into the host also, which interferes with the immune system of the pupa.
The poor moth or butterfly pupa doesn't stand a chance!

You may have seen dried up, open or yellow fluffy pupae under your gutters. This is the work of an ichneumon. The larvae of the wasp hatch, and eat the moth or butterfly pupa from the inside out.

Fascinating insects, and strangely beautiful, in (like I've already said), an evil way...

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