The Secret Burial Ritual of the Butterfly (iPhone X in slow motion)

While taking a nature hike by The Indian River Lagoon in Fort Pierce Florida I came across a puzzling ritual. In a funnel shaped depression in the sand sat a motionless butterfly. Another butterfly of the same species vigorously hovered overhead. It beat its wings hard enough to move granules of dirt over the other and painstakingly covered it completely.

Almost Buried (alive?)

Had I witnessed the touching send off to a deceased soul mate? Or the buried alive torture of a despised adversary?

If there are any entomologists with the answer please advise. It was a hauntingly beautiful yet disturbing sight that begs for an explanation.

The video was shot on an iPhone X using the Slow Motion video mode (1080p HD at 240fps). Worth watching if just to marvel at the wings in motion and wonder what instinct is at work here.

Video Link: Burial Flight of the Butterfly (slow motion)