Datana ministra - Yellow-necked Caterpillar Moth

The Yellow-necked Caterpillar feeds on a wide variety of woody plants. They are highly gregarious.
Durham Co., NC 8/24/2013.

Durham Co., NC 8/24/2013.

Durham Co., NC 8/24/2013.

These are on Willow Oak (Quercus phellos). When threatened, Datana caterpillars assume a typical C-shaped defensive posture (see the caterpillar at lower right).
Durham Co., NC 8/24/2013.

Durham Co., NC 8/24/2013.