Come into my parlour.......

......said the spider to the fly!
Back to work today, which was a bit of a shock after such a lovely holiday with such wonderful weather!
I noticed our ceanothus (we use for indicator experiments) was in full flower, and my cue to pick and freeze some for next year. As I started cutting it I saw this crab spider Misumena vatia sitting on the inflorescence, lying in wait for a poor unsuspecting insect.
According to Wikipedia, these spiders may be yellow or white, depending on which flower they choose to hunt on, young females which may hunt on a variety of flowers can change colour at will to blend in with the flower colour.
They change colour by secreting a liquid yellow pigment into the outer cell layer of the body. on a white base, this pigment is transported into the lower layers so that inner glands filled with white guanine become visible. The colour change from white to yellow takes from 10 - 25 days, from yellow to white about 6 days.
The yellow pigments have been identified as kynurenine and 3-hydroxykynurenine.
Impressive active camouflage don't you think???