Milkweeds were covered with these tiny yellow oleander aphids, and swarms of variegated ladybeetles both adult and larvae, were right there amongst them, feeding on them one by one. This is a non-native species and according to Bug Guide, they were first reported in North America from Quebec, Canada (Gordon, R.D. 1987. The first North American records of Hippodamia variegata (Goeze) (Coleoptera: Coccinellidae). Journal of the New York Entomological Society 95: 307–309. JSTOR).