Mystery Creature

[sanderdieltz]

Hello, my name is Mike

I need some help identifying a creature we found in our 75 gallon salt water aquarium. We have several "live" rocks we bought from a local pet store along with a few fish, some hermit crabs, and a couple of snails. The rocks have been in the tank since January 2006. Recently we found two additional creatures in the tank. One is a small crab (1 inch across) which is very secretive and the other appears to be a set of long tentacles or arms that only emerge at night. When the lights are turned on the tentacle quickly retreat back into the rock. Attached is a link to a video of it. Any help would be greatly appreciated. YouTube - Mystery Creature Needs Identification

 

[neilanh]

That's cool, kinda.

Welcome to AA! Sorry, I have no idea what that is.

 

[melosu58]

Moved to the SW ID forum.

 

[Innovator]

It would be best to either get a really good photograph of the arms or at least describe them to us. My guess is a serpent or brittle star, but without a detailed description it's anyone's guess

 

[newfound77951]

That would be my guess too, as it looks too large to be a spaghetti worm.

 

[Brad.Sedore]

it looks very similar to the sponge that i have... at least i thought it was a sponge... its not as big as yours... the tenticals stick out about 3 inchs in about 5 spots (thats why i didnt think it was a star) and they stick back in as soon as the antic comes on

-Brad

 

[roka64]

Are they smooth or bristly? What color?

 

[Brad.Sedore]

mine?

mine are white smooth and translucent ...

 

[roka64]

LOL, no the OP.

 

[sanderdieltz]

The tentacles appear to be smooth and opaq most of the time. Sometimes they appear to have some black speckles on them. They are the same diameter for most of its length than taper near the very ends.

 

[Innovator]

Next time you see the arms out, don't turn the light on and slowly slip your hand in the tank and feel them. If you are lucky maybe it will latch on and you can carefully pull the mystery creature out, unless of course its main body remains in the liverock.

 

[sanderdieltz]

Still Photo of creature

I've attached a photo of the creature. I'm trying to get a better picture but it's been pretty elusive lately. This photo was taken at about 2:30am

 

[Kurt_Nelson]

...and slowly slip your hand in the tank and feel them. If you are lucky maybe it will latch on and you can carefully pull the mystery creature out...

8O

You're a brave man, James!

 

[ThrowedToad]

IMO it is a large brittle star. I am no expert but mine seems use the same types of movements when I feed. I have seen it's tentacles come out of 3 or 4 different holes in my LR. Good luck!