Irukandji jellyfish
Irukandji jellyfish (/ˌɪrəˈkændʒi/ IRR-ə-KAN-jee) are the smallest and most venomous jellyfish in the world—and the most venomous creature on Earth. They inhabit the marine waters of Australia, Florida and the U.S.A. They are able to fire their stingers into their victim, causing symptoms collectively known as Irukandji syndrome. Their size is roughly a cubic centimetre (1 cm3). There are about 16 known species of Irukandji: Carukia barnesi, Malo kingi, Malo maximus, Malo filipina and Malo bella are the most well known.
The symptoms of Irukandji syndrome were first documented by Hugo Flecker in 1952. They were named after the Irukandji people whose country stretches along the coastal strip north of Cairns, Queensland. The first of these jellyfish, Carukia barnesi, was identified in 1964 by Jack Barnes; to prove it was the cause of Irukandji syndrome, he captured the tiny jelly and allowed it to sting him while his son and a lifeguard observed the effects. He was lucky and they only ended up mildly sick. Australian Toxinologist Jamie Seymour made a documentary about the jellyfish called 'Killer Jellyfish'.
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