Pink Sea Slug with Flower-Like Ornamentation

[CalmSeasQuest]

I thought I had already noticed all my surprises and hitchhikers, until this guy (or gal) showed up last night. I apologize for the low quality of the pics, it was in a difficult area to photograph and moved from sight pretty quickly (a pretty speedy slug.)

It's about 2" in length, has 2 large antenna in the front and a "flower-like" protuberance on the top of the rear section of it's body. It's bright pink in color (much brighter than portrayed in the low-light photos) and transparent (you can clearly see it's organs and digestive track.) It appears to be grazing on algae and I haven't seen it display any interest in any livestock.

It's actually very beautiful - Anyone have a clue what it is?

 

[SushiGirl]

Looks like some kind of nudibranch (the flowery butt is a giveaway!), but in a cursory search I can't find one just like it.

 

[mscarpena]

It is very difficult to ID nudis. If it appears to be eating algae the keep it, but watch to make sure it does not cause any trouble.

 

[greenbean36191]

It's a dorid nudibranch of some sort, though not one I immediately recognize. It definitely doesn't eat algae as no nudibranchs are herbivores. Most of the dorids feed on sponges or tunicates. You can rest assured though that this is not a coral predator, so it can stay in the tank.

 

[CalmSeasQuest]

Thank you very much for your assistance.

I noticed it about 6 months ago in my sump, but it was much smaller. I thought it was some type of sponge as it seemed sessile at the time. It's since grown remarkable. I'm pleased to see it doesn't pose a threat to any corals as it's quite beautiful and is a nice addition to the tank. There are plenty of sponges in my tanks, so hopefully it won't starve.

I also found a very large ribbon of eggs (1.5" circle with .25" ribbon width.) that I assume came from this Nudi - I've seen never seen a Nudi or egg ribbon this large.

 

[pagojoe]

I think it's Hallaxa michaeli, which is known only from southeastern Australia, according to the Sea Slug Forum. It would be interesting to know where it hitched from, if it's that species. See if you agree?

http://www.seaslugforum.net/find/hallmich

Cheers,



Don

 

[CalmSeasQuest]

Thanks Don,

That's very close. I didn't notice any white specks and my guy is brighter pink in color, but overall it's very similar.

I have quite a few Acans that likely originated from that area - The strange thing is I found him in my sump. It must have been attached to some live rock or rubble. In support of the idea that the coloration is diet based - I do have many pink sponges in my tank.

Thanks again for the research.