Camouflaged Caterpillar

The advantage of a newly planted woody plants is that they are short enough to watch closely. We picked up this native Beach Plum (Prunus maritima) from a local nursery last year. The owner couldn't sell it - not showy enough.

I was checking the plant out every day because the blossoms were attracting a large variety of pollinators. Then on this day I had my head and camera in the plant for probably 30 minutes. I finally saw it...

There was a caterpillar! It was frozen in a perfect TWIG pose. I didn't know what it was at the time, but later determined it to be a Red-Spotted Purple Butterfly.

With a little more searching I was able to find a second one. But the next day, no luck. Maybe they went off to pupate, maybe a bird or other predator saw them better than me, but more likely I was staring right at them and not seeing them.