id of possible anemone needed    9/10/12
Hi there. I hope you guys can help me with my query. I am based in U.K and have a 240l soft coral reef tank. I recently bought a small rock with a small colony of yellow polyps on it, amongst the polyps I spotted several lime green polyp type growths ranging in size from the largest at approx  0.5cm to the smallest which are not much bigger than a pinhead.
<Mmm, do you mean mm? Not likely, but half a centimeter is about a fifth of an inch... not a pinhead>
unfortunately over the last couple of months due to ill health I was unable to care for my tank and the yellow polyps just faded away and disappeared leaving an empty rock except for these unidentified polyps. one thing I noticed was sometimes the rock appeared devoid of anything on it so they can obviously retract into the rock which got me wondering what these things were so I posted in the Forum that I'm a member of and I was told they thought it  was a nuisance anemone possibly mojano,
<Mmm, no; don't think so>
now  when I first acquired my live rock 16 months ago I had a couple of mojanos on a rock which were correctly identified to me and by searching the net I was able to confirm this is what they were, these new ones look nothing like a mojano to me but more resemble a Zoanthid
<I agree. Umm, read here: http://www.wetwebmedia.com/zoanthid.htm>
or Palythoa except for this retracting behaviour.
<Zoanthids can contract>
 I have searched the net looking for information but cant find anything to give me a definite identification, although rock flower anemones also seem to get mentioned in the same breath as mojano. I find these small "whatevers" to be quite attractive but having been told they could become a nuisance I'm undecided on what to do, as yet I don't have a sump that I can remove them to. I have attached the best picture that I have been able to get of the biggest one. Really hope you can help me with
this................Kevin
<A beauty. And I do concur w/ your assessment; but would keep them. Bob Fenner>