Box Jellyfish are pale blue and transparent and bell or cubed shaped with four distinct sides, hence box jellyfish.
Measuring up to 20 cm along each side of the cube or bell, the Box Jellyfish has up to as many as 15 tentacles on each corner which can be 3 metres in length with up to 5,000 nematocysts (stinging cells)..
You have virtually no chance of surviving the venomous sting. The pain is so excruciating and overwhelming that you would most likely go into shock and drown before reaching the shore.
So don’t go swimming alone!