Zoea is the larval stage that commonly follows hatching in many crabs.
A zoea is a small, free-swimming crustacean larva with prominent appendages and spines. In many crab species, eggs hatch into zoeae rather than miniature versions of the adult. The larvae drift or swim in the plankton while feeding and developing.
After one or more zoeal moults, a crab typically enters the megalopa stage. The megalopa has a more recognizably crab-like body and begins the transition toward the juvenile form. The exact number of larval stages varies among crab groups.
Zoea should not be confused with nauplius, an earlier larval form common in several crustacean lineages, or with a veliger, the characteristic larva of many molluscs. These names describe distinct developmental forms, and marine biologists use them to track major changes in body structure and lifestyle.