Thursday, 11 September 2014

Sun!

This week has been a bit of a surprise: mist in the early morning followed by absolutely clear blue skies all day. Quite delightful, really.

I have been examining my local Hawthorns for miners and came up with this rather interesting specimen:

Stigmella perpygmaeella mine on Hawthorn

It's the mine of the micromoth Stigmella perpygmaeella, which is new to my species list. At point A (the head of the mine) we can see the miner (yellow larva with oval head). But at point B we can see another, different, larva. This second larva has the look of a hymenopteran about it (round shoulders, tapering body) so it will be either a sawfly larva or a wasp larva of some sort. It is clearly heading towards the miner, so it looks like we have a predatory larva in the mine. I knew that miners could be parasitised by Braconid or Chalcid wasps, but this is an entirely new relationship. More research....

While I was working the Hawthorn, I found a few nymphs of the Hawthorn Shieldbug:

Final instar nymph of Hawthorn Shieldbug
This is the fifth and final stage of the nymph: at the next metamorphosis it will be the adult.

Capitalising on the good light, I went up to the local heath to see what I could find. Devils-bit Scabious is one of the latest plants to flower, and the path was lined in purple.

First to catch my eye was this pale pink variant:

Pink Devils-bit Scabious
I have seen this sport before, but it seemed there more around than usual this year. It looks like the pale colour doesn't put off the pollinators.

This shot shows another oddity which I see from time to time:

Viviparous flower of Devils-bit Scabious
The bud at the top is a viviparous flower growing out of the flower below it. It isn't a branch, because the stem arises from inside the lower flower. Not quite sure why this happens.

Here's a shot of the hoverfly Episyrphus balteatus on a normal flower:

Episyrphus balteatus on Devils-bit Scabious
I noticed this cluster of Russulas from the path side and immediately thought "Russula mairei", which is common everywhere around here, but then I realised there were no Beeches around:

Russula emetica - The Sickener
The trees above are Fir and Pine and the mushrooms are growing through Sphagnum. This is classic habitat for Russula emetica, which I have been hunting for perhaps 10 years. This habitat is perfect for it, so I wonder why it has taken so long to get here. New to my species list, at last.

Russula emetica - The Sickener
Russula mairei is known as the Beechwood Sickener, but Russula emetica is known as The Sickener, as you might guess from its specific name.

2 comments:

Gill said...

Fantastic page - that shieldbug looks as though it is stitched together doesn't it?

The viviparous flower is interesting - why does any flower do this? You might remember a few years ago I had a whole patch of white clover that produced leaves instead of flowers - maybe similar? I'm guessing some chemical signal that's gone wrong. I've not seen this on devilsbit (yet?!). Is the pollinator a little hoverfly?

Sickener - agreed - to me it is always a slightly brighter red than the beech one, as well as different habitat. You often see it eaten by something (slugs?) so it doesn't seem to sicken everything.

stuart dunlop said...

Gill, yes I think the nymph looks like shoe-laces. Not quite sure why it's built like that. The pollinator is a small hoverfly, probably Melanostoma sp. And yes, the Sickener is certainly a brighter, more intense, red than the Beech one.