Even though sting rays skeleton is soft cartilage, they can crush mussel and snail shells in their jaws. They can exert a force equivalent to a 25 kilogram weight sitting on your hand.
Box Jellyfish, a jellyfish found in Northern Australia waters, has tentacles that each contain up to 750,000 nematocysts. The tentacles are raised and lowered allowing 'fishing' at various depths.
