These conspicuous and distinctive orange-and-black caterpillars feed openly, usually on Common Ragwort.

The Cinnabar moth is one of the most easily recognised moths, flying during the day in many open habitats and sometimes in gardens. Sometimes in late August, adult moths may be seen flying alongside fully grown caterpillars. The caterpillars have ravens appetites and will sometimes strip complete plants of their leaves, leaving only the stalks standing. The caterpillars climb down to pupate in a cocoon in or just below loose debris on the ground, where they spend the winter.