Iridescent/ blue sea lettuce?

[daikaijureefer]

I have this macroalgae growing on some live rock I got from Marco rocks in the keys.

It’s hard to get a good photo because it’s near the back of the tank in a small patch of light. It looks a lot like green ulva/ sea lettuce (which is also growing on the same rock) but smaller leaf shapes and instead of being green, it is an iridescent blue. It almost looks like a mushroom coral.


Probably the best picture I got of it:







Again sorry for the poor photo quality it’s the best I can do with what I’ve got (iPhone manual focus)

 

[KrisReef]

I can’t make it out, sorry.
It might be?
The growth pattern kind of looks like daisy polyps or something similar, or possibly a sponge? Try to search images online to find what you can see that I/we can not see clearly in your images.

 

[daikaijureefer]

I can’t make it out, sorry.
It might be?
The growth pattern kind of looks like daisy polyps or something similar, or possibly a sponge? Try to search images online to find what you can see that I/we can not see clearly in your images.

It’s definitely a plant. That much I can tell for sure. This photo zoomed in a bit, you can see the leaf growth pattern is almost identical to green sea lettuce, just a bit smaller.

To the eye, it looks just like a sea lettuce just smaller and bluer. It’s thin leaves just like sea lettuce.

 

[daikaijureefer]

I can’t make it out, sorry.
It might be?
The growth pattern kind of looks like daisy polyps or something similar, or possibly a sponge? Try to search images online to find what you can see that I/we can not see clearly in your images.

I believe I found it online! Thanks to your suggestion I tried a reverse image search with a few keywords and this came up:


Fauchea laciniata:
https://calphotos.berkeley.edu/cgi/img_query?enlarge=0000+0000+0305+0003
Looks a lot like it.

 

[KrisReef]

I believe I found it online! Thanks to your suggestion I tried a reverse image search with a few keywords and this came up:


Fauchea laciniata:
https://calphotos.berkeley.edu/cgi/img_query?enlarge=0000+0000+0305+0003
Looks a lot like it.

I think that you are looking at the wrong item in the image? The Fauchea is the RED algae in the image, and the blue looking stuff, and your additional posting description makes me think you have one of the Dictyota, maybe
this one?
https://www.samarineguide.com.au/taxon/205/

 

[daikaijureefer]

You’re right this is not a red algae. It looks a lot like it could be a Dictyota.

I think that you are looking at the wrong item in the image? The Fauchea is the RED algae in the image, and the blue looking stuff, and your additional posting description makes me think you have one of the Dictyota, maybe
this one?
https://www.samarineguide.com.au/taxon/205/

 

[ThisIsTheWay]

Unfortunately I am of no use in trying to identify it. However, I gotta say that the blue is really pretty and now I have a new macro algae to add to my wishlist :P

 

[KrisReef]

Unfortunately I am of no use in trying to identify it. However, I gotta say that the blue is really pretty and now I have a new macro algae to add to my wishlist :P

I believe that dictyota can become a nuisance algae in many instances.

 

[sixty_reefer]

You’re right this is not a red algae. It looks a lot like it could be a Dictyota.

That’s definitely Dictoya. It’s fairly invasive also.

 

[daikaijureefer]

Anybody have advice on what eats dictoya? None of my CUC touch it including the emerald crab.

It’s not out of control and trimming it every couple weeks seems to keep it at bay. Something caused a bunch of it to die off quickly for a couple of days but then it stabilized and there’s a few patches that won’t really go away.