Nudibranch ID please

[jpcaram]

I found this guy on one of my zoas (big hardy colony) that has been closed for a week now. I'm assuming it is a nudibranch.

It also has "babies" or larva that will become babies (on the right).

I also see a similar one that is red on another zoa that has been closed for a while.

Is this a harmful one? I easily pulled this one out with a pipette. I can start looking closely and pulling them out, but I'd rather not kill these cool looking things if they are safe.

Thanks!

 

[RockBox13]

I found this guy on one of my zoas (big hardy colony) that has been closed for a week now. I'm assuming it is a nudibranch.

It also has "babies" or larva that will become babies (on the right).

I also see a similar one that is red on another zoa that has been closed for a while.

Is this a harmful one? I easily pulled this one out with a pipette. I can start looking closely and pulling them out, but I'd rather not kill these cool looking things if they are safe.

Thanks!

It’s a Zoanthid eating nudibranch. That’s a strange looking one though. Start removing any ones that you can. Can you remove any of the zoa rocks to dip them? Whether you do a freshwater dip or use something like Melafix, try to find any eggs and remove them. I’m not aware of a treatment that kills adults and eggs at the same time. n the aquarium, If you have a soft toothbrush or something similar you can brush the eggs off.

 

[ISpeakForTheSeas]

Baeolidia palythoae or the below would be my best guess at the moment:

In this case, I know it's an Aeolid nudibranch; my best guess would be Aeolidiopsis/Baeolidia harrietae (there's some dispute around what genus the critter should fall into).

Either way, if my guess is correct, it's a known zoanthid eater, and it takes the zooxanthellae from its prey and stores it for use in its own body.

Out of curiosity, though, why do you say those lumps on the right on larvae/babies?

 

[RockBox13]

Those types of Nudibranch will leave eggs on polyps that look like this.

 

[jpcaram]

It’s a Zoanthid eating nudibranch. That’s a strange looking one though. Start removing any ones that you can. Can you remove any of the zoa rocks to dip them? Whether you do a freshwater dip or use something like Melafix, try to find any eggs and remove them. I’m not aware of a treatment that kills adults and eggs at the same time. n the aquarium, If you have a soft toothbrush or something similar you can brush the eggs off.

Maybe it looks strange because I had it just in a drop of water on a microscope slide for a while. Perhaps it got cold?

Many of my zoas are big colonies on rocks. What are my options? One by one? Using a pipette is pretty easy to remove the adults.

 

[Labridaedicted]

Oh boy, yeah, if you can't remove the rocks to remove them it's gonna be a long and tough battle. The adults can be turkey basted out and the eggs can be manually removed when you see them.

I found frequent fw dips to kill adults and scrubbing with a soft bristled brush was best for removal the one time I had them.

Some species of Halichoeres wrasses also have a track record of eating them (notably yellow coris [my go to vote for pest control wrasse] and melanurus)

 

[jpcaram]

Baeolidia palythoae or the below would be my best guess at the moment:

Out of curiosity, though, why do you say those lumps on the right on larvae/babies?

Oh, because at one point they were away from the adult, they have the same colors and pattern, and they move! I have some video, but it was too large to upload here.

I just pulled this other one from another coral this afternoon. Similar structure but different color, and it also has what I've been calling "babies":

 

[jpcaram]

They clearly came with my last purchase. So perhaps they haven't spread around so much . Positive (and naive) thinking?

 

[ISpeakForTheSeas]

Oh, because at one point they were away from the adult, they have the same colors and pattern, and they move! I have some video, but it was too large to upload here.

I just pulled this other one from another coral this afternoon. Similar structure but different color, and it also has what I've been calling "babies":

Interesting- a lot of people upload their videos to YouTube then link them here.

Do the babies have visible rhinophores (the "horns" on the head like the adult has)?

 

[RockBox13]

Some people have used Flatworm Exit from Salifert to kill adults and then repeat that treatment again in about a week to deal with the eggs that hatch during that time. Check on those instructions though. I haven’t had to treat them in tank for a long time, there are probably some other solutions available now. I also vote for a Melanarus or Coris wrasse. If you have a decent LFS, see if they will get one in and put a couple nudibranchs in there with the wrasse to see if they will eat them.

 

[jpcaram]

Interesting- a lot of people upload their videos to YouTube then link them here.

Do the babies have visible rhinophores (the "horns" on the head like the adult has)?

No horns. You can see the babies very clearly on my last picture.

 

[ISpeakForTheSeas]

No horns. You can see the babies very clearly on my last picture.

Without the "horns," those are most likely autotomized cerata - when nudibranchs like this feel threatened, they drop those little, bubbly sacs on their back, and the dropped sacs wiggle around to attract predators to attack them instead of the nudibranch.