Thursday, 30 July 2009

Occasional names

I saw what appeared to be a minute, strangely-coloured ladybird on the Ragwort and it was only when I blew up the image that I could identify it as a teneral (freshly emerged, and not yet fully-coloured) 10-spot Ladybird - Adalia decempunctata. These are about 3-4 mm. long, so that makes the beetle below it about 1 mm long.

Few Tachinids can be successfully named from pictures, but this is one of them. Eriothrix rufomaculata (named after the distinctive red marks on the abdomen) is a bit of an enigma: it is readily identifiable, but its host and larval stages are unknown. I only ever see it on Ragwort, so Cinnabar moth comes easily into the frame, but the fly has never been reared from them.

Moving on from one nameable beast to another, the ichneumonid on the left is Amblyteles armatorius. Its size can be easily reckoned from the neighbouring Tree Wasp - Dolichovespula norwegica. It's really good to be able to show these close relatives side by side. They aren't particularly dangerous to each other, but the ichneumonid is keeping a very close watch on the wasp - note the antennae.

That wasn't a chance shot, by the way: I noticed the ichneumonid was gradually approaching the Tree Wasp and waited until it was right next to the wasp before I rattled off a few shots.

Angelica is a major nectar source for many insects at this time of year. Female ichneumonids are swarming over the florets, refuelling before they go off in search of hosts.

Evacanthus interruptus is one of the more scarce leaf hoppers in this area. I might see one or two per year.

Phyllonorycter moths are minute - only a couple of millimetres long as adults. This is the mine of Phyllonorycter maestingella, on Beech. The larva tucks the lower surface of the mine a few times, contracting it and pulling the upper surface into a dome, thereby making a tube to live and feed inside.

This glimpse of the emerging Blackening Waxcap - Hygrocybe nigrescens - reminds me that the fungal season is almost upon us. It's time to dust down the fungal part of my brain.


Gill said...

"It's time to dust down the fungal part of my brain." Yup - I noticed a few purplish russulas pushing through the leaf litter yesterday. That waxcap looks like a heart, don't you think?

And aren't those long ovipositors remarkable - is that so she can stay a safe distance from the prey I wonder?

Stuart said...

The longer ovipositors are used where the target larva is buried deep in a flowerhead (like a thistle or knapweed) or even in wood. The ichneumonids that have very short ovipositors usually target easier-to-reach leaf-feeding larvae.

Anonymous said...

Great shots of these wasps! Although that Dolichovespula is actually norwegica not sylvestris. (note the red markings on T2) It's the yellow palearctic form and the nearctic norwegica species we have here has a black and white colouration with red. Also D. sylvestris never has such an enlarged clypeal marking as shown on the one you have here. The "anchor" shaped marking on the clypeus is a reliable indication of it being norwegica alongside with the red markings on the gaster.

Stuart said...

Thanks, anon, identification updated.