Greetings! This past weekend, I found two of these caterpillars munching on my backyard grapevine leaves. I captured them and took them inside to observe. When I returned from running errands, both had escaped from captivity and where toodling around on the kitchen floor! So, back outside they went to fend for themselves… I have looked at all 9 (!) of the caterpillar pages on your WONDERFUL site to no avail! The closest match I could find on the internet is the Grapevine Moth, Phalaenoides glycinae, from Australia. But I don’t live anywhere near Oz, we are about 40 miles north of Philadelphia, PA. Any ideas? I have attached 2 photos, a side view and a top view, I hope they are satisfactory for a positive ID!! Thanks for maintaining such a cool site!!
This looks to us like the caterpillar of the Eight Spotted Forrester Moth, Alypia octomaculata. According to BugGuide, Grape is a food plant.