Box Jellyfish : 7 Facts of The Most Deadliest Jellyfish

1. Box jellyfish have 20 ocelli or simple eyes. These eyes doesn’t give images and only detect light and dark. They total have 24 eyes where the other 4 are the complete eyes with retina, cornea, and lenses.

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2. Box jellyfish can weight up to 2 kg and their tentacles can reach up to 3 meters. Each of its tentacles has 500,000 cnidocytes that contains a harpoon-shaped mechanism to inject venom.

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3. Unlike any other jellyfish, the box jellyfish actively hunt their prey. Their venom is used to protect them from predators such as batfish, butterfish, and  hawksbill turtle.

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4. They are an excellent swimmer, they can swim and achieving speeds up to 1,5 to 2 meters per second or about 4 knots / 7.4 kilometers per hour.

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5. Researchers found that Box jellyfish venom could cause hyperkalemia, a condition that lead to cardiovascular collapse and death as quickly as within 2 to 5 minutes. The venom could kill at least 60 people.

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6. A thumbnail box jellyfish called Irukandji jellyfish can cause the victim suffer from physical and psychological symptoms called Irukandji syndrome. Irukandji syndrome causes backache, tachycardia, sweating, pulmonary edema and worst is a feeling of “impending doom”. This psychological symptom makes the patient thinking that they are going to die and in some extent begging the doctor to kill them to get over with.

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7. The box jellyfish sting people actually not triggered by touch but by the chemical they found in our skin. So it is best to wear full diver suit when in May or October which believed to be the peak months of this jellyfish. Different from what people believed; urine, lemon juice, fresh water, alcohol, cold packs and other substance could actually hasten the release of the venom rather than disable it. For the treatment, it is better to seek a medical professional.

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