Live rock creature ID.

[jfreeman]

There's a creature that lives in my live rock that only comes out when it's very dark. When the light goes on it contracts immediately. It's about 6 inches long and has 2 flaps on the end that sticks to the spot on the outside of the rock. When the lights go on the flaps release the rock and it contracts back into the hole. It moves too fast to get a photo. Any ideas on what it might be?

 

[ReefMonkey13]

From your description, it sounds like a mantis shrimp.

Google it and see if the pics match what you have seen.

 

[swayd]

+1
Campout and get a picture for us:spy:

 

[Dalmatia]

There's a creature that lives in my live rock that only comes out when it's very dark. When the light goes on it contracts immediately. It's about 6 inches long and has 2 flaps on the end that sticks to the spot on the outside of the rock. When the lights go on the flaps release the rock and it contracts back into the hole. It moves too fast to get a photo. Any ideas on what it might be?

It's not a mantis shrimp, they are very easy to spot at 6" and don't retract but retreat. Sounds like a tube worm? Nothing to be worried about but a pic would help a 100%

 

[SeahorseKeeper]

Try to look at the tank in the dark with a flashlight. Try putting a red film over the light. It may keep it from retracting so you can snap a pic.

 

[ritter6788]

It's not a mantis shrimp, they are very easy to spot at 6" and don't retract but retreat. Sounds like a tube worm? Nothing to be worried about but a pic would help a 100%

Agreed. A 6 inch mantis shrimp doesn't come as a hitchhiker and wouldn't hide or retract.

 

[jfreeman]

Definitely not a mantis shrimp.

 

[Reef Fever]

euclid worm maybe?

 

[jfreeman]

 

[jfreeman]

Got a picture of it as it was contracting back into the live rock.