The Sea Waspor jellyfish box is one of the deadliest animals to itch in the sea. The marine wasp has a large transparent body shaped like a box or bell, which can be as large as a bucket, and can weigh up to five pounds. A group of 16 long semitransparent tentacles come out from under the hood of the jellyfish box. Millions of spicy capsules cover each of the tentacles. Spicy capsules discharge lethal poison into the skin of any creature that touches them. Children who have been bitten by the marine wasp have died within minutes of being bitten.
Each tentacle has about 500,000 cnidocytes, needle-shaped spears that inject venom into the victim. In Australia, fatal poisonings are most often perpetrated by the largest species of box jelly, Chironex fleckeri, due to its high concentration of nematocysts.
The box of jellyfish actively hunts their prey (zooplankton and small fish), rather than drifting like true jellyfish. It is capable of speeds up to 4knots (1.8 m / s).
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Box jellyfish are known as the “suckerpunch” of the sea not only because their sting is rarely detected until the venom is injected, but also because they are almost transparent.
Once a tentacle of the jellyfish box adheres to the skin, it pumps the nematocysts with venom into the skin, causing stinging and agonizing pain. Successful use of Chironex antivenom by members of the Queensland Ambulance Transport Brigade showed that acetic acid, found in vinegar, deactivates box jelly nematocysts that have not yet been discharged into the bloodstream (although not Will relieve the pain). The common practice is to apply generous amounts of vinegar before and after the tentacle is removed. Removal of additional tentacles is usually done with a towel or gloved hand, to prevent secondary itching. The tentacles still bite if they are separated from the bell, or if the creature is dead. Removal of tentacles without prior application of vinegar may cause uncooked nematocysts to come in contact with skin and fire, resulting in a higher degree of poisoning.