I found this beetle in our yard in Clifton, VA. The beetle came out of our flower bed next to the house. I think it is a Spotted Pelidnota. Other names for this beetle includes grapevine beetle or spotted June beetle. I think it is a female because this beetle was light-colored.
Observed this pair on a trail not here in Clifton but at River Bend park near Great Falls.
Clif Fairweather, a Naturalist with Audobon Naturalist Society, responded to this post suggesting “that the little beetle might be taking cantharidin from the blister beetle toincorporate into its own chemical defense” Whatever the intent was of the little beatle attached to larger one it struck me as some sort of strange symbiosis