Insects grow by metamorphosis. In incomplete metamorphosis, an insect egg hatches, and a small nymph comes out. The nymph usually looks just like the adult insect but is much smaller. Nymphs do not become pupae before becoming adults. They just grow larger. They moult through various stages called instars.
Some insects have nymphs that are aquatic, which means they live in water. These nymphs look very different from the adults. Dragonflies have nymphs that live in water, such as in lakes and rivers. Nymphs that live in water are sometimes called naiads.
Some insects that are nymphs when they are young are grasshoppers, cockroaches, true bugs and dragonflies. nymphs are in the middle of the lifecycle of alot of insects like grasshoppers and dragonflies and lots more nymphs are insects that start to form in water and when they get to adult size they come out of the water and mostly live on land in a food chain the nymph would come after the trout and then it would eat the phytoplankton.