I recently found this peculiar bug on my buddleia (butterfly bush). I had never seen it before. Coincidentally I also found a dead painted lady butterfly and two dead bees.
So I captured one of the bugs and placed it in some rubbing alcohol to examine it closer. Digging through my insect books I discovered that this is an "ambush bug". They are predatory insects and will capture other insects and suck out their body fluids. That explains why the butterfly's and the bees' bodies were intact. I don't mind the ambush bug killing the bugs that harm my plants but the butterflies and the bees???!!! I draw the line there! I will be doing some ambushing of my own! Mom