hemimetabolikus

Hemimetabolous, also known as incomplete metamorphosis, is a type of insect development characterized by gradual changes throughout the life cycle. Unlike holometabolous insects that undergo complete metamorphosis with distinct larval, pupal, and adult stages, hemimetabolous insects hatch from the egg as a nymph. Nymphs are essentially miniature versions of the adult insect, differing primarily in size and the absence of fully developed wings and reproductive organs.

As a hemimetabolous insect grows, it sheds its exoskeleton multiple times through a process called molting. Each molt allows the nymph to increase in size. Between molts, the immature stage is referred to as an instar. Throughout these instars, the nymph gradually develops. Wing buds, which are external precursors to wings, become progressively larger with each successive molt. Eventually, after the final molt, the nymph transforms into a sexually mature adult.

Common examples of insects that exhibit hemimetabolous development include grasshoppers, cockroaches, dragonflies, damselflies, true bugs, and termites. The nymphal stage typically occupies a similar habitat and diet to the adult, though there can be some differences. This developmental strategy is considered ancestral among insects, with complete metamorphosis evolving later in the insect evolutionary history.