How does a butterfly chrysalis differ from a moth cocoon?

The primary difference between a butterfly chrysalis and a moth cocoon lies in their construction and composition. A chrysalis is the naked pupal stage of a butterfly, formed by the insect's own hardened body without an external silk covering. While most true butterflies pupate this way, there are rare exceptions, such as the satyr and parnassian butterflies, which do construct cocoons.12

In contrast, a cocoon is a protective silk casing spun by many moth larvae before they pupate. These structures are often constructed from silk alone, but they may also incorporate materials such as larval hairs, chewed wood pulp, leaves, or other debris for added protection. While many moths form these cocoons in soil, leaf litter, or under bark, some species pupate in the soil with little to no cocoon at all.12

In summary, the chrysalis is the exposed, transformed body of the butterfly itself, whereas the cocoon serves as an external, protective shell created by the moth larva.12