Need help identifying coral.

[Difficult09]

It looked like bubble algae on my live rock and sat like that for about a month. Now its opened up. Not sure what type of coral it is. I do have some blastos, favia, gsp, hammers, and toadstool. Looks nothing like what I have in there. If i were to guess I'd say it was a zoa but never had any in this tank.

 

[DangerDave]

Looks like a big green paly, you'll know more when it fully opens...

 

[ddelmonaco]

Paly or common hitchhiker zoa. Lot of LFS have these on their colonies of other corals in grow out tanks and sometimes they can get attached to other frags. nothing to worry about, see how it grows out could be cool