Some jellyfish species carry venom strong enough to cause severe pain, heart complications, and nervous system disruption.

Jellyfish belong to medusozoans, or animals producing medusae, and include today's box jellies, hydroids, stalked jellyfish and true jellyfish. Medusozoans are part of one of the oldest groups of ...

Beachgoers are urged to avoid touching the cube-shape jellies.

Jellyfish could be much smarter than scientists previously thought, asserts a new study published in the journal Current Biology. Poisonous Caribbean box jellyfish can learn at a far more complex ...

A Hong Kong university team said it has discovered a new species of box jellyfish in the city's Mai Po Nature Reserve, the first discovery of the venomous species in China's waters. Baptist University ...

Researchers confirmed Atlantic box jellyfish washed up on North Padre Island and warn beachgoers that even dead-looking jellyfish can still sting.