Agapostemon bee on squash flower

If ever there were a prettier bee, I'm not sure that I've seen it in this life. What we have here on a squash flower is a green bee that appears to have been crafted from burnished metal. The unlikely bit of gorgeous natural sculpture is a member of the bee family Halictidae, a group whose members can vary from being solitary to semi-social. This one, a member of the Agapostemon genus, tends towards the solitary end of things in the nesting department—they nest underground—perhaps because having a congregation would cause too much sparkling and, hence, draw too much attention to the nursery. I see them often glinting in the sunshine, and that always draws my eye, and, of course, camera lens. While they're still on the prowl, I should probably start netting at least a few to learn their identities down to species, but, so far, I've been content to just collect pictures.