I don’t even know where to start with this one

[trevorhiller]

Just received a shipment of rock from gulf live rock—let the IDing fun begin!

Can anyone tell me what this could be? It’s large, about 3” long. It has a kind of calcified exterior, but gives a little bit when you poke it. Doesn’t feel like a clam shell. The whole exterior looks like rock, but feels soft inside when you poke it.

I haven’t noticed it moving yet, but you can move it with tongs as you can see in the video.

Mysterious Live Rock Organism

youtube.com

 

[Sean Clark]

no idea...

 

[gavinz]

Just received a shipment of rock from gulf live rock—let the IDing fun begin!

Can anyone tell me what this could be? It’s large, about 3” long. It has a kind of calcified exterior, but gives a little bit when you poke it. Doesn’t feel like a clam shell. The whole exterior looks like rock, but feels soft inside when you poke it.

I haven’t noticed it moving yet, but you can move it with tongs as you can see in the video.

Mysterious Live Rock Organism

youtube.com

Have you ever seen it open up at all or anything?

 

[reddevilant]

I had something that looked kind of similar. Came to the conclusion it was a tunicate. The picture is close up so it's hard to see but it appeared the same way yours does when the tunicate would close up. Leave it alone for a while and see if a couple tubes open up.

What is this alien? Tunicate?

I recently added some macro algae to my tank that came in already attached to a rock.....or at least what I thought was a rock. I had noticed the “rock” was softer, almost sponge like. I have other macros whose holdfast structures had similar textures so I figured that’s what I was feeling...

www.reef2reef.com

 

[DaJMasta]

Gulf live rock? A big red tunicate, like this one, but looks deflated and normally they would react to touch:

Red Sea Squirt

 

[trevorhiller]

I’ve looked through a lot of ID threads and I don’t even know where to start on this thing. Don’t really want to yank it off until I know what it is.

 

[HuduVudu]

Just received a shipment of rock from gulf live rock—let the IDing fun begin!

Can anyone tell me what this could be? It’s large, about 3” long. It has a kind of calcified exterior, but gives a little bit when you poke it. Doesn’t feel like a clam shell. The whole exterior looks like rock, but feels soft inside when you poke it.

I haven’t noticed it moving yet, but you can move it with tongs as you can see in the video.

Mysterious Live Rock Organism

youtube.com

It's a clam that is closed. The attachment is it's foot.

 

[trevorhiller]

Gulf live rock? A big red tunicate, like this one, but looks deflated and normally they would react to touch:

Red Sea Squirt

I just got the rock from gulf live rock and put it in the water about 30 minutes ago. This could be! Color is wrong, but shape and texture seems right. Although this is calcified on the outside, like coralline has grown on it, but squishes if you poke it.

 

[DaJMasta]

The ones I've had have some give to them but have a firm structure - sort of like a natural sponge for bathing but without all the holes. It's got a reddish tint, would be stressed, and has a fair bit of dust on it - you may be surprised at the color it ends up!

 

[trevorhiller]

It's a clam that is closed. The attachment is it's foot.

The exterior doesn’t feel like a clam shell. It has a lot of give.

 

[trevorhiller]

This is like opening a mystery box of aquarium goodies, so fun!

 

[ying yang]

I've seen a few " what's this threads " on newly purchased live rock and seen in them posts some share links from the vendor on the common hitch hikers that comes with the rock so maybe look on your sellers website to see if got one or look through " what's this live rock threads " to go to the link that others shared as often seen them.
Good luck and hope you enjoy watching and finding all the wonderful / interesting little critters you will find ha ha

 

[ying yang]

Gulf Live Rock.com

gulfliverock.com

Found this on Google,not looked at ot so not sure if anything similar to what you got,but may help you with other stuff or help others who ordered same rock ^_^

 

[WheatToast]

Gulf Live Rock.com

gulfliverock.com

Found this on Google,not looked at ot so not sure if anything similar to what you got,but may help you with other stuff or help others who ordered same rock ^_^

Great resource! I have found this website to be helpful as well:
http://web.archive.org/web/20210510215846/https://www.tbsaltwater.com/thepackage/organisms.html

 

[WheatToast]

I had something that looked kind of similar. Came to the conclusion it was a tunicate. The picture is close up so it's hard to see but it appeared the same way yours does when the tunicate would close up. Leave it alone for a while and see if a couple tubes open up.

What is this alien? Tunicate?

I recently added some macro algae to my tank that came in already attached to a rock.....or at least what I thought was a rock. I had noticed the “rock” was softer, almost sponge like. I have other macros whose holdfast structures had similar textures so I figured that’s what I was feeling...

www.reef2reef.com

Gulf live rock? A big red tunicate, like this one, but looks deflated and normally they would react to touch:

Red Sea Squirt

Agreed! Tunicates are an incredibly diverse group of animals.
https://www.kpaquatics.com/product/colored-tunicate-sea-squirt/

 

[SlugSnorter]

Just received a shipment of rock from gulf live rock—let the IDing fun begin!

Can anyone tell me what this could be? It’s large, about 3” long. It has a kind of calcified exterior, but gives a little bit when you poke it. Doesn’t feel like a clam shell. The whole exterior looks like rock, but feels soft inside when you poke it.

I haven’t noticed it moving yet, but you can move it with tongs as you can see in the video.

Mysterious Live Rock Organism

youtube.com

Tunicate or cucumber maybe. maybe a sea hare? kinda looks like Dolabella auricularia. where is the live rock grown?

 

[trevorhiller]

I've seen a few " what's this threads " on newly purchased live rock and seen in them posts some share links from the vendor on the common hitch hikers that comes with the rock so maybe look on your sellers website to see if got one or look through " what's this live rock threads " to go to the link that others shared as often seen them.
Good luck and hope you enjoy watching and finding all the wonderful / interesting little critters you will find ha ha

Thank you, I did check out their frequent hitchhiker page, but this just doesn’t seem to match any of them.

Gulf Live Rock.com

gulfliverock.com

Found this on Google,not looked at ot so not sure if anything similar to what you got,but may help you with other stuff or help others who ordered same rock ^_^

Thanks

Tunicate or cucumber maybe. maybe a sea hare? kinda looks like Dolabella auricularia. where is the live rock grown?

Honestly it looks most like the sea hare, but seems firmly attached and I think sea hares are pretty mobile. I guess I’ll see if it moves or reinflates in the coming days.

 

[Duncan62]

Just received a shipment of rock from gulf live rock—let the IDing fun begin!

Can anyone tell me what this could be? It’s large, about 3” long. It has a kind of calcified exterior, but gives a little bit when you poke it. Doesn’t feel like a clam shell. The whole exterior looks like rock, but feels soft inside when you poke it.

I haven’t noticed it moving yet, but you can move it with tongs as you can see in the video.

Mysterious Live Rock Organism

youtube.com

If you leave it alone does a mouth or other opening open?

 

[trevorhiller]

If you leave it alone does a mouth or other opening open?

Nothing I’ve seen.

there’s lots of other clams on the rocks, they open and close when you touch them. But this thing is just kind of there.

 

[Gulf Live Rock]

Its a red sea squirt. I need to add it to my id page. Thanks