ID request

[SpareParts]

Hello,
Bought a small piece of live rock from an LFS a couple weeks ago because it appeared to have attached a small white sponge. My "fuge" is actually a secondary display, filled with sponges and other filter feeding inverts. Well, after I got it home and a few days later, several "mouths" appeared on the sponge. Each mouth or orifice is fringed with filaments, like polyps. It is soft, like a sponge and recently began to take on a brownish tinge (maybe from algae, I dunno). Any care to take a guess at ID?

 

[TheH]

They look like retracted zoanthid polyps.

 

[aentrop]

zoas/palys/or button polyps

 

[SpareParts]

I think I can see why this thing might look like a button polyp or zoo/paly. The thing that's throwing me, is that it is one continuous entity. Not individual stalks like I'd expect in a Zoo, but something like a marshmallow with multiple orifices. Thanks for looking!

 

[TheH]

Post it in the zoa forum, it really looks like zoas that were infected with some kind of bacteria/fungus-like thing. I had something like that happen to one of my zoa frags a long time ago. Frag of about 5-6 polyps turned into a white marshmellow.

 

[Elysia]

What about Palythoa caribaeorum or something similar? Its an encrusting zoanthid. Sometimes called sea mats. You don't see the tiny polyp tentacles when the polyps are retracted. I had some for a while, but eventually they were shaded and slowly died. Which was unfortunate, as they were kind of cool.