Giant ichneumon wasps

mehampson

Giant ichneumon wasps (Megarhyssa macrurus) -- there's a dead tree near me that's basically an ichneumon nursery, so I've been taking an interest in them lately. They're parasitoid wasps that grow on (or in, I think) the larvae of other wasps, which kills the host in the process. Think 'Alien'. This sequence was taken over a few weeks, and I finally saw the females laying on this last trip.


A male, waiting for a female to 'hatch' out of the tree -- it took about three weeks of watching these guys to get one in a position where I could get this angle on him.


A female, who's found a larval wood wasp buried in the tree. She's maneuvered her ovipositor into its hole and is laying an egg on it. For reference, with the ovipositor, the females are about 4" long. Males are like 1.5".


There were three or four females laying eggs on this tree while I was there recently. After they hatch, a larval ichneumon wasp feed on the larval wood wasp it was layed on, and the adults will emerge from the tree next year.


These are males competing to fertilize a female who hasn't actually emerged from the tree yet. You'll see one or two with their abdomen in the wasp's hole at a time, and up to ten or so trying one after the other.

I've got a few more here if you're interested -- really cool, creepy animals.

GOLDENORFE

great shots of a superb looking wasp
phil

Lord Vetinari

Lovely shots- wonderful looking Ichneumon.
Thought these normally parasitised wood boring beetle larvae ?
Brian v.

mehampson

Thank you. According to what I've found, this particular species of ichneumon targets the larvae of the pigeon tremex (Tremex columba), a siricid wasp -- one website claims they destroy 40% of tremex larvae every year but that might be a regional statistic. I'm not sure if the tremex is their only host or just their most frequent, though, and other ichneumon species definitely target beetles.

And I didn't realize it when I posted, but another neat thing is that the wasp in #2 is actually withdrawing her ovipositor. The tip of the abdomen kind of stretches out with that white membrane you can see as she withdraws it.

IPClark

What an amazing looking creature. Nat Geo would love this.

Beautiful shots, stunning colours and fantastic detail.

Skippy

mehampson wrote:

Giant ichneumon wasps (Megarhyssa macrurus) -- there's a dead tree near me that's basically an ichneumon nursery, so I've been taking an interest in them lately. They're parasitoid wasps that grow on (or in, I think) the larvae of other wasps, which kills the host in the process. Think 'Alien'. This sequence was taken over a few weeks, and I finally saw the females laying on this last trip.

A male, waiting for a female to 'hatch' out of the tree -- it took about three weeks of watching these guys to get one in a position where I could get this angle on him.

A female, who's found a larval wood wasp buried in the tree. She's maneuvered her ovipositor into its hole and is laying an egg on it. For reference, with the ovipositor, the females are about 4" long. Males are like 1.5".

There were three or four females laying eggs on this tree while I was there recently. After they hatch, a larval ichneumon wasp feed on the larval wood wasp it was layed on, and the adults will emerge from the tree next year.

These are males competing to fertilize a female who hasn't actually emerged from the tree yet. You'll see one or two with their abdomen in the wasp's hole at a time, and up to ten or so trying one after the other.

I've got a few more here if you're interested -- really cool, creepy animals.

Great shots

I love the first Shot.

You know what I love about the MACRO forum?
Not only do you see some of the most incrediable shots you've ever seen in your life.... it's so educational too.

We get to see creatures we never knew existed,
photographed so closely, most would never see these creatures this close in their life time.

Thank you for sharing your Wasp shots with us .... Skippy
.