Hanging by one claw, this green lynx spider (Peucetia viridans)
dropped the butterfly she had been feeding upon and caught this
colorful wasp. While she fed, the wasp was swarmed by tiny micro-flies
called "freeloader flies". These tiny flies feed upon the
prey of the spider, sometimes even hanging out with and riding around
on the predator. These uninvited dinner guests are called
kleptoparasites! I have also seen them on the prey of assassin bugs.
(Thanks to Bugguide.net for the identity of the flies.)
*Alternative unscientific "Bob's world" explanation: the wasp died peacefully in it's sleep and the little grim reaper flies (forager minions of the spider queen) picked it up and flew it to her so it wouldn't go to waste!
(I really need the clouds & wind to go away so I can get back to wildflowers ;-)