The larvae are one of the kinds of woolly bear caterpillars, and the very young of the leopard moth are two-toned, just like the better known woolly bear that is black on the ends and chestnut colored in the middle.

The small caterpillar shown above at left is feeding on water hyacinth, and I've noticed them on sedum, but they mostly eat plantain, which is common enough in our lawn.

The woolly bears get pretty large (up to about 2 inches long) and the bigger ones are all black, with dark red bands between segments. When threatened, the caterpillar usually rolls up into a ball with all its spines sticking out. However, some of the woolly bears are a bit more aggressive and will stretch out as if reaching to ward off an attacker. They also excrete feces, which is a common defensive action among caterpillars.

When the larva creates its cocoon, it mixes its spiny hairs with silk to make a tough covering. Although the caterpillars are large, they don't do much damage in the gardens because they are never very numerous.