All right, here's my two cents.
Looks like an H Crispa to me, due to the leathery tan column and what appears to be white spots on the column.
Additionally, it has placed itself with its foot sunk into the sand at the rock line edge, which is exactly where my crispa is the happiest. Your clowns wouldn't have moved it, it would have moved itself there. They can move all over the place and surprise the heck out of you in the morning. My RBTA climbed the glass and took up residence by the overflows for a while.
It looks pretty badly beat up.
Also, your sig line says that you've got a 12 gallon nano. There could be any number of things bothering your H Crispa, including water fluctuations, water quality, etc, in addition to your clowns loving it a little too much.
Your tank is far too small for an h crispa. My H Crispa is approx 14 inches across today and that is without maximum tentacle entension.
I wish you and your nem luck, but don't think it's going to make it.