Need help identifying an animal

[Cindy0519]

This creature appeared in my aquarium a few weeks ago. Does anyone know what it is? It is the size of a quarter and craws around on the live rock. It appears to have several legs.

 

[ramseynb]

It sound like a brittle starfish maybe but it's hard to say. Can you take a picture? I mean, a spaghetti worm also could fit that description.