Something growing on my Halloween crab

[TylerE]

Spotted this on my crab this morning and noticed little black tentacles coming out from underneath. Anyone have any idea what this could be?

 

[TylerE]

Sorry should add that it's the little white shell thing with the brown center.

 

[TylerE]

Could it be a baby snail?

 

[SHNICI]

It look like a limpet snail, or barnacle (one of both)

 

[TylerE]

Are they safe or should I remove?

 

[SHNICI]

Are they safe or should I remove?

the Barnacle is feather duster, it's reef safe, if it's limpet can be one which grow too big, or if there is hole on it it can be Keyhole limpet, then most aren't reef safe.
Do you see it ever move from that spot, or it grow all the time there on it ? If it's statically on the shell, then is Barnacle. Time by time you can see it's opening a bit and fan like feather is going out and back in, grabbing food from the water column.

 

[TylerE]

I haven't noticed it moving but I do notice black tentacles coming out every once in awhile.

 

[SHNICI]

I haven't noticed it moving but I do notice black tentacles coming out every once in awhile.

then you got it, compare it if you wish from the link there
And you can find easy the particular SP

 

[TylerE]

What link? And what does sp stand for? Sorry I'm new to the hobby. No fish in the system yet.

 

[SHNICI]

What link? And what does sp stand for? Sorry I'm new to the hobby. No fish in the system yet.

this MSG

It look like a limpet snail, or barnacle (one of both)

If you see something like text in orange that mean here is a link to website so that's it :
https://www.google.com/search?sxsrf...AhXDnFwKHQKCB4sQBSgAegQIKxAq&biw=1440&bih=789

Google Search

www.google.com

but is too long and we use different way to short it, or to implement it in the text not to have ugly looking text with code

 

[TylerE]

O ok. I scrapped it off and here is a better picture of it. Not sure if this helps anymore.

 

[TylerE]

Here is another picture. Can anyone help me?

 

[Strangewaterchange]

Was going to say possible baby snail or limpet but I'm intrigued by the black appendage or creature coming out. Does the black part move around or go back in? If so could you maybe get video of it moving?

 

[Saltyreef]

Keyhole Limpet. Agree the black tenticles is weird....

 

[SHNICI]

the black think is part of the internal flesh, when he scrap it off of the snail (hermit crab) shel and brake it a bit.

 

[TylerE]

Here is a video of it moving

 

[SHNICI]

that's not a snail, it's crustacean.

#reefsquad

 

[TylerE]

Are they harmful? Should I just get rid of it?

 

[SHNICI]

Are they harmful? Should I just get rid of it?

this one will die, once taken off it will die, you don't need to remove them, they are filter feeders, just can cover some area sometimes, but I personally do like them (if they aren't too big over 1")

 

[TylerE]

Ok good to know. Thanks for all the help with this.