larvalstage

A larval stage is an immature form of an animal that lives after hatching, birth, or another early development event and before reaching its adult or final juvenile form. Larval development is widespread across many animal groups and the larva often differs markedly from the adult in size, shape, habitat, and lifestyle.

Larvae typically have distinct feeding strategies and may occupy different environments than adults. They are often free-swimming, planktonic, or parasitic, and they frequently disperse to new areas. Morphology is usually specialized for larval life. Common examples include caterpillars and sawflies in insects, maggots in flies, tadpoles in amphibians, and larval forms in various marine invertebrates such as mussel veligers or echinoderm pluteus larvae.

In insects, two major developmental patterns involve metamorphosis. Holometabolous species undergo complete metamorphosis, with a larval stage, a pupal stage, and an adult form (for example, butterflies, beetles, and bees). Hemimetabolous species experience incomplete metamorphosis, where nymphs resemble smaller versions of the adult and molt into sexual maturity through successive molts, often without a pupal stage (as in true bugs, grasshoppers, and many crustaceans). Some groups also exhibit direct development, where juveniles resemble miniature adults from birth.

Ecologically, larval stages can influence survival, feeding relationships, and dispersal, thereby shaping population dynamics and evolutionary trajectories. Larval forms are frequently used in taxonomy and phylogenetics because they can retain distinctive features useful for distinguishing lineages.