Brachiolaria

A brachiolaria is the second stage of larval development in many sea stars; it follows the bipinnaria. Brachiolaria have bilateral symmetry, unlike the adult sea stars, which have a pentaradial symmetry. Starfish of the order Paxillosida (Astropecten and Asterina) have no brachiolaria stage, with the bipinnaria developing directly into an adult.