Irukandji jellyfish: "This is a 10 out of 10 pain that you are going to hang onto for probably six to 12 hours. There's usually severe vomiting, nausea, stomach cramps and about 10 to 15 per cent of patients end up with cardiac problems."
http://mobile.abc.net.au/news/2018-01-09/irukandji-found-in-stinger-drags-at-fraser-island/9315674?pfmredir=sm
