The collective power of those tiny suction cups is incredible! The starfish has no trouble prying open shellfish for dinner.
I got a shock once, picking up a plum size urchin I had never seen before.
It had vertical rows of blunt, stony spines it uses it peg leg around the reef, with areas between the spines populated by many hundreds if not thousands of hairlike tube feet, each tipped by a suction cup.
As I held it for about 20 seconds admiring the deep red color of the hair like tube feet, these things were busy attaching to my fingers.
When I attempted to release it - my fingers might as well have been in set concrete.
It's quite a shock to realize you are helpless, and the accompanying shot of adrenaline is the only reason I was able to tear my fingers free.
I was absolutely astounded at the strength of this beautiful little urchin...
Then the dark side of my humor kicked in and I finned over to a a friend who was diving with us, and handed it to him.
He admired it for a bit, and then went into Spasm trying to free his hand. I was laughing so hard I had to hold my regulator in my mouth.
I helped him free himself and put that formidable creature back on the reef, as we both swam away with a newfound respect for these mighty tube feet!