Weird worm to ID

[striker3636]

Anyone seen one of these before? Came in on a pipe organ I got...definitely a worm, has little antenna at one end and he moves around the tank like a worm... Weird anemone like tentacles on its body...Sometimes it will curl up in a ball and looks like a little anemone with the feelers stuck out. He's about 1.5" long...
Any help with an ID would be appreciated.

[greenbean36191]

It's a nudibranch of some sort (probably in the aeolid family); not a worm, but a slug. Judging by the camoflauge and the fact that it was on your organ pipe I would say it's a coral predator (many of them are).

[striker3636]

He's been in the tank for 6-8 months now, and I havent noticed anything getting eaten... he spends most of his time on the live rock, never seen him on a coral yet, and he's grown a bit since I've had him, so whatever it is he eats, he must be getting it...

[striker3636]

The reason i thought he was a worm is that if you look down inside the tentacles, you see the body of a worm, fairly skinny, that all those tentacles are attached to.... All the nudi's I've seen are more flat and wide and, well, slug-like...

[masson]

I have one like that also , does yours have little sticky arms that come out?

[striker3636]

Not that I have ever seen

[ClamIAm]

It definitely looks like some sort of nudibranch to me. If you have a lot of spare time on your hands you can look through the photos Here and see if you can identify it.

[greenbean36191]

If you have a lot of spare time on your hands you can look through the photos Here and see if you can identify it.

To save you some time search the genera Phyllodesmium and Pauleo. Also have a look at Limenandra fusiformis. If you don't think any of those match what you have I'm almost certain that it is at least in the suborder Aeolidina, so that narrows it down to only a thousand species or so.

I'm by no means an expert on nudibranchs, and these are just my best guesses as to an ID.