The last time I came in contact with one of these, it was in Hawaai about 40 years ago.  We were on an outrigger off shore and we all had to go over the side so they could bail out the water from the boat (some people were not holding up their end of rowing). LOL
I thought I felt ground and that we were possibly on a sand bar, so I put my foot down and stepped on one.  We were actually over a coral reef.  The pain was incredible and I ended up in the emergency room.  Another guy in our group also ended up in there with me because he cut his foot on coral & bleeding (fortunately no sharks were near by), he was on the other side of the boat.
Needless to say, I was very careful handling this beautiful creature.  Unlike the black/blueish one I stepped on, this was almost all white and beige.