Box jellyfish

Class of cnidarians distinguished by their cube-shaped medusae

Box jellyfish (class Cubozoa) are cnidarian animals distinguished by their box-like (i.e., cube-shaped) body. Some species of box jellyfish produce potent venom delivered by contact with their tentacles. Stings from some species, including Chironex fleckeri, Carukia barnesi, Malo kingi, and a few others, are extremely painful and often fatal to humans.

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