another "what is it!"
 

found this creeping out from behind some liverock, at first i thought a pale bristle worm, then i noticed it was getting much longer, and the things on the side of the body were actually legs like a cattepillar.

got a few decent pics, it stretched about 4 inches out of the rock with the end not in sight. it has a flat head/beak looking front.... the pics tell the rest...

http://i242.photobucket.com/albums/f...3/100_1614.jpg
http://i242.photobucket.com/albums/f...3/100_1613.jpg

any guesses on my several million legged hitchhiker?

i should also add, it visibly has a head, with eyes (i think), its responsive to movement (recoils under the rock), and the legs move in a paristaltic fashion like a catterpillar or centipede

Standard, government issue, bristle worm.

i wasnt aware bristle worms have legs... i thought they only had spiney/puffy protrusions from their sides...

this one has millipede-esque legs that move and grip

Government issue thats funny. Here is a little article on bristle worms, you might find it useful.

ive been looking on WWM to get an idea, from this site here (http://www.reefkeeping.com/issues/2003-03/rs/index.php) it shows quite a different head then what i have seen on this worm... are there other species with different heads?

the one in the picture has a disc like head with visible eyes at the back of it, it has no antanae

Third sentence in: "This group of animals is diverse, with over 10,000 species known, and undoubtedly many thousands of species are remaining to be discovered and scientifically described."

I'm guessing that it is a Eunicid family worm. Many people refer to these as bristle worms, although they are quite different than the traditional bristle worms that we all have.

Distinquishing characteristics of the Eunicid family are 5 distinct "antennae" surrounding the head/mouth. They also typically retreat into rockwork with lightning speed when disturbed. Yes...centipede like legs.

While some Eunicids can grow to enormous length and are the stuff of Aquarium lore (Oregon Reef Eunicid over 7 feet long...), others are harmless detritus feeders. Keep you eye on it and see what it eats.

Here's one of my favorite photos of "Max" who lived in my 30 gallon hex for 5+ years and was probably over 2 feet long. He was strictly vegatarian.
http://i142.photobucket.com/albums/r...s/100_0865.jpg

Oh yes..I forgot...really nasty jaws that they use to grab and retreat.