hey guys. i wish i could post a pic for this, but i dont own a camera. i bought a piece of live rock from my local store about 2 weeks ago, and it's great. lots of life on it, and one of those forms of life i'm not familiar with. there are two "tentacles" coming out of a very small hole in the rock that come in and go out snatching small particles that come in contact with them. they move about the rock pretty deliberately, not just moved by the current. the "tentacles" are very small, one is about 1/2 an inch long and the other is about 1 inch, and they are very small in diameter, and just a dull grey/brown color. and sometimes they both completely retract into the rock. what could this creature be? is it anything i need to be worried about?? thanks in advance!!
Glad I could be of help. And micro brittle stars are one of my favorite hitchhikers so you shouldn't worry about them. I have about 30-40 of those guys in my 10G and an unkown number in my 35G. They don't do any harm, but are very cool to watch and do a great at cleaning up your sand bed and eating uneaten food. I have two types. The banded macro stars like hiepnotik showed and the white ones. From my experience the banded ones grow larger than the white ones (definitely not full on serpent star size though). But you are more likely to see the white ones come out of their cave. They move pretty fast when they want to.