Maybe the last thing a Flesh Fly sees would be a lovely emerald green:
Jumping Spiders are very cool (unless the dewpoint is above 70). I saw one this week just outside the kitchen window. It was jet black except for three or four white spots on the abdomen. Looking closer, what struck me was the beautiful color on the "fangs" or chelicerae. Perhaps it was Phidippus audax.
The spiders that, in a way, help people get very close looks at butterflies tend to be Crab Spiders. They lay in wait on flowers to grab unwary insects...as do Ambush Bugs (check out an action-packed photo). An immobile butterfly on a flowerhead could prove to be in the clutches of one of the above critters. Queen Anne's Lace, a.k.a. Wild Carrot, is in full bloom right now. A small brownish butterfly "nectaring" on it could well be one of the Hairstreaks -- usually a Banded, but in the past I've noticed Hickory and even Juniper (Olive) Hairstreaks utilizing this flower. It's definitely Butterfly Season right now, and I'll be leading several butterflying-by-bike trips over the next couple weeks -- let me know if you're interested!