Orangestriped Oakworm Caterpillar
Fifth instar caterpillars are black with orange stripes. They have prominent spiny horns on the second segment of the thorax. There are also smaller spikes on the remaining segments. They feed on oak trees during August and September. If caterpillar populations are large enough, they can cause severe defoliation of oak trees.
''Anisota senatoria'' is a Nearctic member of the family Saturniidae and subfamily Ceratocampinae. It is one of the more common Saturniids, reaching pest status occasionally in the northern parts of its range. As they are late-season feeders, however, they do little lasting damage to their hosts .
It is very similar to ''A. finlaysoni'' in southern Ontario and ''A. peigleri'' in the southern USA.