It's a bit of a surprise when one of these come up in your occy pots...This one was very small. Two or maybe three would fit into a match box.
A close up of a ring
I used to see these around the rock pools at Watson's Bay in Sydney as a kid (littlejoe) ; then when I found out a soldier had picked one up , been bitten and died, I was terrified it gave me nightmares and never went back to those rock pools again!
Very nice shots!
Yes, they do exhibit the blue when they are threatened. These little guys can often be found around many harbour beaches in very shallow water (5cm or less!).
We often see them around Parsley Bay, Camp Cove, Neilsen Park and Clifton Gardens on night dives.