Leafhoppers actually just suck the juices out of the leaves and don't eat them so you tend to get brown circles of death spots in the leaves if they were the culprit. Japanese beetles, tend to eat everything in the leafs. In your picks, it looks like the veins in the leaf are still intact. So I would guess some type of caterpillar? Could be Coma butterflies or some other moth or butterfly larva?