indicates that, owing to the number of rhopalial nerve cells and their overall arrangement, visual processing and integration at least partly happen within the rhopalia of box jellyfish. The complex nervous system supports a relatively advanced sensory system compared to other jellyfish, and box jellyfish have been described as having an active, fish-like behavior.

Depending on species, a fully grown box jellyfish can measure up to 20 cm along each box side (30 cm in diameter), and the tentacles can grow up to 3 m in length. Its weight