If you’ve ever walked past a grapevine and noticed the leaves looking more like lace than greenery, you may have stumbled upon the work of the Eastern Grapeleaf Skeletonizer (Harrisina americana). These small, spiky caterpillars may be tiny, but they leave a big mark—literally. From their bristly defenses that can irritate your skin, to their habit of feeding in groups and turning grape leaves into skeletons, these insects are full of surprising quirks.