Alien Critters

greeneyedlady

Duchess of Comedy
Jul 4, 2002
173
0
0
MD, USA
Okay so I spotted three of these things I'm guessing they are worms in my tank the other night, (had on the moon lights) I've looked all over but can't figure out what they are. There is no way I'm going to be able to get a good picture of these guys cause they disappear as soon as the lights come on.

I don't think they are harmful as they seem pretty skittish around any of my inhabitants that come near.
They appear to be attached to my rock and they stretch themselves out and grap chunks off the rock and then swallow it, retract and start the whole process over. They are brown in color and like I said appear to be some type of worm. I wish I could describe them better but they are pretty nondescript. Anyway I sat and watched them the other night for about an hour just to make sure they wouldn't go for the fish and such in my tank. Fascinating little critters one was able to stretch itself from 1/2 inch to about 3 inches in length.
When a crab walked by it immediately retracted and did not reappear for a good 5 to 10 minutes until the crab had passed.

I was just wondering if anybody had ever seen these little "aliens" and if they had a name?
 
I'd place a modest bet that they're peanut worms, aka sipunculans. Most of the body is in a hole in the rock, and they extend an "introvert" out to gather food.
 
hey cool, of course I can't see the part that is "buried" in the rocks to get a look at the whole thing. From the descriptions that I read after looking it up (having a name really helps) and the pictures of it I would say that is my little "alien":D

Thank you so much mogurnda;)
 
i got two of these on the live rock that i bought a few days ago, amazingly fun to watch :)
 
yeah caz that's why I sat and watched them for an hour the other night:D
 
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