Lepidoptera: Hesperiidae
Mesodina hayzia
One doesn't have to spend a lot of time observing butterflies before it becomes obvious that they like dung.
Horse dung, dog dung, whatever, it doesn't seem to matter. There is obviously something attractive about it and possibly beneficial to the butterfly's diet.
This Eastern Iris Skipper has its proboscis inserted in bird dung that has fallen on bracken.