After saying I'd do this for a good long while I finally pulled the rock from my tank and went on a worm hunt. I was after the "big scarey thing" that I could see through its trail under the tank and found 2 other worms.
The big one I found I've identified using Wet Web Media as a peanut worm. I'm torn between putting it back and not. Even after reading an article by Shimek saying they are detrivores, I'm not sure if this thing could be partly to blame for the pile of snail and hermit shells along "death alley". If it matters, this one is putty colored when retracted (about 2") and gets paler tan to white as it stretches itself out (maybe 6-8"). Is it reasonable to drop blame on this worm or did I dig him out of his home for no good reason?
Here's a reference picture from Wet Web Media that looks close enough to the worm I pulled: http://www.wetwebmedia.com/WormPIX/P...sipunculid.jpg
Under Tank shot: http://photos.smugmug.com/photos/i-4...-4WFjZZD-L.jpg
The next worm I found was a white worm. The most I can say about this one is it's long thin and white. Roughly 3"-4" fully extended and thread thin. No identifying marks or name tags that I can see. I'm probably going to dump this one since I can't identify it.
The last worm, which was the first one I found, is some sort of eunicid worm. It had made a tunnel on the bottom of a rock from the substrate and had attached snail shells to each end. As soon as the snail shells on one end were disturbed it shot to the other end of the tunnel. It's roughly 4" and hasn't stopped searching/exploring the little plastic tub its been caged in.
And of course pictures!
http://www.smugmug.com/photos/i-dQJs...-dQJsTrC-L.jpg
http://www.smugmug.com/photos/i-mbQn...-mbQnV8Q-L.jpg
I also found other (older?) sediment tunnels on various other rocks without the snail shell entrance/exit doors. Do you think I missed a few worms or do the eunicid type worms move from rock to rock and tunnel to tunnel?
The type of worm I did not find were bristle worms. I think I may have found one that I broke in half while disturbing the white worm (pictured) but that's it. I'm not sure how concerned I should be about not finding a worm...