Saturday, 9 May 2009

Tiny gap in the rain

It had rained for 48 hours and I spotted a small gap in the cloud, so I drove the two miles to this part of the hedgerow (Leg 2) as fast as I could. By the time I arrived it was raining again.

Five minutes later.....

I glimpsed this insect half-hidden under a leaf. What do you think it is? (the major - and huge - clue is clearly shown).

Not Bumblebee, but a Bumblebee mimic, the hoverfly Eristalis intricarius:

Notice how the scutellum (the orange bit) is wide and hairy, giving the appearance of a golden band, like a bumblebee. The clue in the first image is the obvious 'loop' in the wing veins....the 'eristalis bulge'.

This is a close-up of the face, showing the tiny antennae and the three ocelli or minor eyes between the main eyes. Many flies, bees and wasps have these extra eyes which are very sensitive to light change, and are used to detect movement.

A rolled leaf is like a magnet to me, and I reckoned this was the home of a micromoth larva. (You can see the ejected frass (dung) to the left of the image).

Sure enough, a little poking and prodding revealed the larva of the Timothy Tortrix micromoth. Notice the areas of buttercup leaf that have been consumed.

This micromoth larva is gravely at risk. Within half a metre of the larva I found two potential predators. First the so-called flower bug, Anthocoris nemorum (about 4 mm long). These are predators of moth, butterfly and sawfly larvae.

And also this wonderful, minute (3 mm.) Ichneumonid. These parasitic wasps also target larvae.

The rain had barely stopped for a minute when three male Orange Tips appeared from under the edge of the ditch. No time to waste when the ladies are expected to be out and about.


Gill said...

Wow! That close-up of the hover's head is incredible! Have you got a new camera / macro lens, or are you just getting very skilled with the one you've got? Turning green....

Stuart said...

Same old Canon EOS 350 with the Canon 60mm macro lens. I guess I'm getting used to it 18 months in.