These two weevils each have white spots on their scutellar areas (not restricted to just the scutellum), but were different in size and color. I supposed they were different species until I saw the dark gray one mount the brown one. That alone is no indication of relatedness, especially in my light arena, where many beetles climb on top of other beetles, especially weevils. But when I saw the rider rapidly stroking the sides of the one on the bottom with its hind legs, I figured this was no happenstance affair. I didn't see them copulate, but I saw enough foreplay for me to place them in the same species.

I saw these beetles in dogbane and yarrow blossoms, and I think they were in some other kind of blossom as well.