Hitchhiker Id?

Can anyone help ID this hitchhiker. It doesn't really move, other than to close up, like a clam or something.
When I got up this morning, he had clamped onto a piece of rock that was nearby.

I was finally able to get a couple good closeups today.....any ideas

Thanks !!!



Another couple pics:

No ideas

He seems to not move during the day. As soon as the LEDs go on or the lights go out, he moves. Climbed halfway up the tank wall and then dropped off and stayed on the sand. Strangest way he moves....he opens the shell a bit, sticks out a long clear "armlike" thing, then retracts it to pull him along.

Strange!

Well, I finally figured what one of my other hitchhikers is. I thought it was some kind of barnacle....but I never saw any cirri coming out to sweep for food.
Well, last night before I went to bed I looked in the tank with a flashlight to check on my new goby.......guess what........the barnacle was fishing for food with his cirri.

My hitchhiker:


Not sure if it is the same species, but it looks very similar to 'balanus perforatus':

its just a barnacle. Noting bad.