PUPA

plural Pupae, or Pupas, life stage in the development of some insects, occurring between the larval and adult stages (imago) in insects exhibiting complete metamorphosis. During pupation, larval structures break down and adult structures form: wings appear for the first time. The adult emerges either by splitting the pupal skin and chewing its way out or by secreting a fluid that softens the cocoon. The process of pupation is controlled by hormones. One of the most commonly recognized pupal stages is the cocoon of butterflies and moths (Lepidoptera). In this protective covering the caterpillar is transformed into an adult. Cocoons may be found hanging from twigs or bushes, hidden in rolled leaves, in underground litter, or in burrows. Some insects spend the winter in this stage.