Thanks Debra. I've seen brown ones, green ones and sort of white ones, but never these bright colored ones. It seems an odd trait to me because they are really visible and most aphids get down in tight leaf growth where they hide. These are way out in the open. They eventually disappear as the growth ages. Unless I see damage, I think I won't bother with spraying. With the other aphids, the foliage shows damage, but the Hosta never has. There aren't very many on the Mandevilla, but it also isn't showing damage. They must be doing something, but I can't detect it. Maybe they are some sort of tropical aphid and I'm overwintering them when I bring the plants inside.
