How are orthopteran nymphs different from adult insects?

Orthopterans, such as grasshoppers, crickets, and katydids, are hemimetabolous insects, meaning they undergo simple or incomplete metamorphosis. Unlike holometabolous insects, they do not have a pupal or resting stage.12

Nymphs generally resemble adults in form, but they differ in several key ways:

• Size: Nymphs are significantly smaller than mature adults.1
• Reproductive Organs: Nymphs lack fully developed reproductive organs, which only become functional upon reaching adulthood.1
• Wings: Nymphs are wingless or lack fully developed wings. While wing pads may appear during later nymphal stages, wings do not become fully functional until the final molt.31

The life cycle of an orthopteran typically progresses through three stages: egg, nymph, and adult. Upon hatching, many orthopterans emerge first as a vermiform larva—an active embryo enclosed in a membrane—before shedding it to become a recognizable nymph. As they grow, nymphs undergo a series of molts, typically ranging from 4 to 13 stages, before reaching their final adult form.1