To overcome this, pupae often are covered with a cocoon, conceal themselves in the environment, or form underground. Pupae are usually immobile and are largely defenseless. In a few taxa of the Lepidoptera, especially Heliconius, pupal mating is an extreme form of reproductive strategy in which the adult male mates with a female pupa about to emerge, or with the newly moulted female this is accompanied by other actions such as capping of the reproductive system of the female with the sphragis, denying access to other males, or by exuding an anti-aphrodisiac pheromone. Pupal mating Mating in pierid Catopsilia pyranthe of male with newly emerged female. Measuring the timing of this emergence is of interest to chronobiologists because the process is regulated by circadian clocks in many species, necessitating different assays to measure eclosion timing. Once the pharate adult has eclosed from the pupa, the empty pupal exoskeleton is called an exuvia in most hymenopterans (ants, bees and wasps) the exuvia is so thin and membranous that it becomes 'crumpled' as it is shed. Prior to emergence, the adult inside the pupal exoskeleton is termed pharate. In fleas, the process is triggered by vibrations that indicate the possible presence of a suitable host. In mosquitoes, the emergence is in the evening or night. Insects emerge (eclose) from pupae by splitting the pupal case. In temperate climates pupae usually stay dormant during winter, while in the tropics pupae usually do so during the dry season.Īdult Hercus fontinalis emerging from cocoon Eclosion of Papilio dardanus Emergence The pupa may enter dormancy or diapause until the appropriate season to emerge as an adult insect. For example, the pupal stage lasts eight to fifteen days in monarch butterflies. The pupal stage may last weeks, months, or even years, depending on temperature and the species of insect. The adult structures grow from imaginal discs. It is during the pupal stage that the adult structures of the insect are formed while the larval structures are broken down.

The pupa is a non-feeding, usually sessile stage, or highly active as in mosquitoes. The pupal stage follows the larval stage and precedes adulthood ( imago) in insects with complete metamorphosis. Pupae may further be enclosed in other structures such as cocoons, nests, or shells. The pupae of different groups of insects have different names such as chrysalis for the pupae of butterflies and tumbler for those of the mosquito family. The act of becoming a pupa is called pupation, and the act of emerging from the pupal case is called eclosion or emergence.

The processes of entering and completing the pupal stage are controlled by the insect's hormones, especially juvenile hormone, prothoracicotropic hormone, and ecdysone. Insects that go through a pupal stage are holometabolous: they go through four distinct stages in their life cycle, the stages thereof being egg, larva, pupa, and imago. Unlike most pupae, tumblers can swim around actively.Ī pupa (from Latin pupa 'doll' plural: pupae) is the life stage of some insects undergoing transformation between immature and mature stages. Pupa of the rose chafer beetle, Cetonia aurata Tumbler (pupa) of a mosquito. For other uses, see Pupa (disambiguation).

Lunar moth chrysalis