Sea-jelly

There were many of these sea-jellies (jellyfish) floating by while we were trying to enjoy the water at Tiwi Beach. But those tentacles. Initially, you would feel a stinging pain where they brushed past, then a tingling and numbing over the next 20 minutes or so, and then, eventually, they would just become itchy rashes taking, in a couple of cases, days to settle down.