I grow a large number of asclepiads, including several varieties of milkweed. They always attract milkweed beetles and Milkweed Tussock caterpillars which munch, no big deal. This year I'm finding the critters on my oleander, hoyas, plumerias and adeniums as well. They aren't really eating them, maybe a bite here and there but to see them crawling all over the plants is unnerving. I realize all are in the Apocynaceae family but in all the years I've been growing these varieties I've never seen them on anything but milkweed. There's plenty of milkweed in my yard so it's not like they are competing for food.