What is this? Long striped legs

[tygger]

Does anyone know what this could be? It comes out from that rock to the left above the yellow polyp and usually at night or when the actinics are on searching for food. It has more than 6 legs that I can count, maybe it's two brittle stars of some type. The legs are at least 6 inches long extended and are mostly clear/whitish with black stripes.

 

[dhoch]

I see the legs, but it's a little hard to tell.

 

My guess is that it's a medusa worm... never seen em in the rock (only sand) before.

 

Dave

[mogurnda]

Yep, looks like a big, juicy terebellid (spaghetti, medusa) worm. Nice detritivore. Most of mine live in rocks or rubble, and send tentacles onto the sand like your photo.

[rocko918]

I have plenty of them as well in my sand bed. They do not seem to harm anything. I have lots of corals on the sand bed. I pull some out from time to time as they multiply quickly. Good feeders.