I don't know of any worm that looks like that off -hand. My first tought was Nudibranch. There are quite a few like this, although I have never seen one this black. Many aeolids look simialr to this, Aeolidacea. Can you get a more of close-up of the head ?
Hey I saved the picture to my computer and opened it with Picture it 9 software increased the brightness 54% and then saw it is a brittle star for sure you just can't see it until you brighten it up .The first picture has on the left the center of the star and then whats left of one of the legs its chopped up in pieces whish i knew how to upload the brightened up photo so you could see as well maybe someone can walk me thru how to do it
Thanks Boomer - it was actually your post about it being something other than a worm that caused a spark in my brain. When I looked back at the picture it dawned on me that it might be a star of somesort.
I photoshopped one of the pics. You can make out the central disk, and the partial arm.
Yes, I see it now, a brittle star and more than likely a member of the Ophiocomidae/Ophiuroidae family (same family different names) and maybe the genus Ophiocoma