Crab Spiders

Found some interesting facts on crab spiders: the remarkable Crab Spider Thomisus onustus has a chameleon-like ability to change colour to match it's surroundings, so it can be white, yellow, pink or variegated in appearance. The change of colour takes about 2 or 3 days to complete however, so it is common to find a spider on the "wrong colour" of flower.

 

Spending several days motionless on a flower head, crab spiders wait for their next meal to fly in they have excellent forward vision, and move immediately and stealthily towards any bee or butterfly which settles on the flower. In contrast, their peripheral vision is poor, so much so that it is possible for a butterfly to settle alongside the spider without being attacked. If on the other hand it is unfortunate enough to walk across the spider's field of vision, the powerful pincer-like forelegs immediately seize the butterfly. The spider then bites it on the neck, injecting it with a paralysing venom which incorporates enzymes that liquefy the butterfly's internal tissues Thomisus onustus then sucks out the body contents of the butterfly, discarding the chitinous exoskeleton and wing.

 

http://www.bbc.co.uk/nature/life/Crab_spider#p003lcv1