Australia and its creatures …. this one has to live here in Nth QLD where the beaches are perfect! The Irukanji is about the size of a thumb nail and becomes invisible with its jelly, see-though appearance in the ocean. These guys are one of the most painful of stings and it has the potential to be fatal. Our beaches are swept for these jelly fish in the mornings and are closed if they are found in the nets. Stinger season runs from November through to May/June approximately! There are optional stinger suits sold around for extra protection.
More information here –http://www.health.qld.gov.au/goodhealthintnq/topics/jellyfish.asp