Breathtaking Metamorphosis: The Saturniidae Moths..

Saturniid caterpillars are large (50 to 100 mm in the final instar), stout, and cylindrical. Most have tubercules that are often also spiny or hairy. Many are cryptic in coloration, with countershading or disruptive coloration to reduce detection, but some are more colorful. Some have urticating hairs. A few species have been noted to produce clicking sounds with the larval mandibles when disturbed. Examples: Luna moth (Actias luna) and Polyphemus moth (Antheraea polyphemus). The clicks may serve as aposematic warning signals to a regurgitation defense.