When I first came across these butterflies, I was a little confused as to which way was up. From several feet away, it looked like they had another bug on their wings but upon closer examination, I realized it was their wing tips. This is called the Hairstreak Butterfly and the wing tips are grown to confuse predators into attacking their wings instead of their heads. The flower upon which its feeding is called the milkweed and is especially known for attracting monarch butterflies.
Nikon D750 | 105mm | f/7.1 | 1/500 | ISO 200
Thanks for looking!