Irukandji jellyfish

Irukandji jellyfish are tiny and extremely venomous jellyfish that inhabit marine waters of Australia and which are able to fire their stingers into their victim, causing symptoms collectively known as Irukandji syndrome. Its size is roughly no larger than a cubic centimetre (1 cm³).

The average jellyfish has stingers only on its tentacles, but the Irukandji also has stingers on its bell. Irukandji jellyfish differ from other box jellyfish species in that they have the ability to fire stingers from the tips and inject venom.

Irukandji syndrome is produced by a small amount of venom and includes severe pains at various parts of the body (typically excruciating muscle cramps in the arms and legs, severe pain in the back and kidneys, a burning sensation of the skin and face), headaches, nausea, restlessness, sweating, vomiting, an increase in heart rate and blood pressure, and psychological phenomena such as the feeling of impending doom. . If left untreated, this syndrome may cause the victim to go into cardia arrest and die within 20 minutes!

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