Just about anything in the ocean that peirces the skin will inflict pain or cause infection ,mostly from bacteria so anything spikey ,BE CAREFUL, I had the spine on a prawns head ,the one right between their eyes stab me under my finger nail and the pain that followed was grim to say the least,could not move my arm for about 2 hours and about 6 hours before the pain started to subside.So keep asking questions and be cautious when handling marine creatures.