These treehoppers, Entylia carinata have been feeding on my Frostweed (Verbesina virginica) all summer, attended by what I believe are Black Carpenter Ants, Camponotus pennsylvanicus. They keep to the underside of the leaves, and if you flip the leaf over, the ants rove onto your hand, sometimes stinging. The hoppers are all adults now, and I brought some leaves inside on a stable surface for detail shots. The ants, unfortunately, run off. The hoppers don't like the exposure either, and begin to move after a bit. As they warmed up, they would walk, then hop, and sometimes fly.