Posted by: scrubmuncher | February 9, 2010

A face only a mother could love (2)…

There’s a small, wingless parasitic wasp (Methoca ichneumonides) that preys on a green-tiger larva by waiting for it to attack before dodging past the fearsome mandibles and slipping into the larva’s burrow. The beetle larva is now the victim and the wasp closes the deal by injecting paralysing venom into its prey’s soft, unprotected body. With an incredible feat of strength and persistence, the wasp drags the limp, albeit living tiger beetle larva to the bottom of its burrow where she lays a single egg on it. She then scoots off, seals the burrow and goes about looking for more tiger beetle larva to punish.

The green-tiger beetle's nemesis - the parasitic wasp , Methoca ichneumonoides (http://delta-intkey.com/britin/images/bent3291.jpg)

Here’s a clip taken from the Life in the Undergrowth showing green tiger beetle larvae catching prey in their characteristic way and a female  M. ichneumonides taking on one of these beastly, ambush predators.

If the beetle larva manages to avoid the attentions of this wasp and other predators then it will reach the point in its life where it can pupate in preparation for its brief time above ground as an adult. Like any other insect that goes through metamorphosis, the contrast between the larva and the adult tiger beetle is amazing. The adult, with it iridescent exoskeleton and bulging eyes is also a predator of small insects, like ants, but it is an active hunter that pursues its prey over the ground with bursts of six-legged sprinting and short, fast flights, eventually getting hold of its victim and dispatching them with its fearsome mandibles.

Cicindela campestris adult

The green tiger beetle adult is quite a sight close up, what with its metallic, iridescent exoskeleton and manic behaviour - Winterton Dunes, Norfolk (Ross Piper)

Cicindela campestris adult

The cruel mandibles of a green tiger beetle trying to find purchase on a finger - Winterton Dunes, Norfolk (Ross Piper)

Advertisements

Responses

  1. What a very tricky thing to film – even for the BBC’s finest in a studio setup presumably!

    • You’re not wrong, Dom. I presume it must have been a studio job as that wasp is pretty rare and you can see what’s going on below ground. By the way, I like your videos, especially the one of the burnet parasitoids. You even managed to get some footage of a Gelis sp. hyperparasitoid. What do you use to get that footage? Is it a DSLR and a macro lens? Ta. Ross

      • Hi Ross. Canon DSLR with 60mm Macro in very windy conditions unfortunately. One very good reason for using a studio if possible!

        Stills here:

        http://www.flickr.com/search/?ss=2&w=26693731@N08&q=hyperparasitoid&m=text

      • Thanks, Dom. I’ve got the same set-up, but I haven’t done much filming with it, apart from through the microscope. Nice stills of the the Gelis sp. by the way.

      • The 600D with the swivel screen is a blessing for macro work and the 3x (lossless) movie crop mode is also very handy – turns the 60mm into the 180mm at a fraction of the price!

      • Thanks, Dom. I have a 60D and I didn’t even know you could do movie crop with it. I’ll have to try it out.

      • I’m not sure if the 60D has the HD movie crop mode does it? Maybe they updated the firmware. The 600D was the best in the range for video when I bought it.

      • I tried it earlier and it does have this function. The telephoto effect is approx 7x with an image size of 640×480, so not HD.

    • Yeah – that’s a different crop mode – I wouldn’t recommend using that one for macro work. The 600D and later models have a 1920×1080 Full HD crop mode at 3x magnification.


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

Categories

%d bloggers like this: