From a distance (less so up close) the coloration of these hopper nymphs reminds me of tiny stormtroopers. They're very striking against the green leaves. The second image shows an all-black variation (assuming it's the same species). And the final image includes a species of Enchenopa. I don't know if the adult is the same as the nymphs, though, as this branch had quite a variety of hoppers on it.