White Banded Crab Spider

Since August 12th at least, this large (larger than a quarter) white bodied spider with a grey V marking and greenish head has devoured at least 4 butterflies, predominantly the larger varieties. It camouflages itself deep in the blooms of my butterfly bush where it waits for it's prey. The strange thing about it, is that it hangs its prey from the blooms as if they are still alive where they remain all day. I have not been able to find any remains of these butterflies in subsequent days. Very odd.