Come into my parlour...

Unlike many of their relatives, crab-spiders do not build webs and rely on camouflage to ambush their prey of flies and bees. The name 'crab-spider' is said to refer to a fancied resemblance to crabs, or to the way such spiders hold their two front pairs of legs, or their ability to scuttle sideways or backwards.

Today's image is a species of crab spider called Misumena vatia which sits on or beside flowers or fruit and grabs visiting insects. Individuals of this species are able to change colour over a period of some days, to match the flower on which they are sitting. This one is a delicate greenish-yellow which tones very well with the wood-spurge flower it's lurking in.

I first spotted the striped yellow Nomada bee, and thought it looked rather strange . I actually touched the abdomen and only then did I see the spider attached to the head end. The spider had obviously just captured its prey, and you can see its fangs plunged through the delicate membranes between the bee's head and thorax, injecting a poison which completely paralyses the unfortunate victim.

The image was taken at Bedford Purlieus NNR, just west of Peterborough. I'd visited to sort out the route of a walk I'm leading there on Sunday afternoon, and to check there wasn't too much mud. I was pleasantly surprised at how dry it was, and how many woodland species were still in flower, including swathes of bluebells and wood anemones. I managed to find locations for many of the rare plants known from the site, so feel quite well prepared. If any local blippers would like to come along, details can be found here.