What Are Earwig Larvae?
As insects, earwig larvae hatch from eggs and are the multiple stages between egg and adult. Since the metamorphosis is gradual, meaning that the hatched immatures look similar to adults, the proper term is really “nymphs.” With some exceptions, the term “larvae” usually means a worm-looking stage that occurs during a species' complete metamorphosis … egg, larva, pupa and adult.
Since earwigs go through simple metamorphosis, the young are called nymphs. Whether an insect species goes through complete or gradual metamorphosis, the various stages of larvae or nymphs are called instars. For example, after an egg hatches, if there are multiple stages before pupae in complete metamorphosis, they would be called the “first larval instar,” “second larval instar,” or “first instar larva,” etc. Likewise, with gradual metamorphosis where the stages look similar to adults and there is no pupal stage, the stages would be the “first nymphal instar” or “first instar nymph,” etc.
The number of earwig nymphal stages will depend on the species. Most species have three to five stages. During this time, the younger nymphs are softer bodied than adults and must have adequate moisture surrounding them in order to survive and move to the next nymphal stage. Their food choice at the time is similar to that of the adults, although for predator species of earwigs, it is less likely that they will aggressively hunt. The species that are not predacious will remain under the wet decaying vegetation or in cracks and crevices. Since they are nocturnal, they are not easily observed during the day unless their resting places are disturbed.
Nymph forceps or pinchers are not as fully developed as the adults' and due to their pliability, they typically are not effective as weapons. Adults use the forceps to capture prey, assist with mating, and to act as defense mechanisms.
As nymphs grow, they outgrow their shells and will have to molt or shed the old shell to allow for the body to grow. After molting into the next instar, the earwig nymph is particularly susceptible to drying out and predators. The final instar then molts into adults, and, as an adult, the insect will no longer grow or shed its shell.