White collared black "worm" ID requested

scolley

ARKSC Founding Member
Premium Member
I recently got some live rock that I'm quarentining. I've put no food in the tank for about two weeks, until tonight. To my amazement one rock had a visitor emerge that I'm hard pressed to identify.

It was worm like in form. Long, round, consistent diameter. Not tapered or anything like that. What emerged from the rock was about 3" long, and possibly 1/4" in diameter. There were clearly some kind of small mouth parts on the anterior end. And it could (did) retreat into it's hole almost faster than the eye can see. But the really interesting part was the color.

It came out in low (but not no) light. Hunger I guess. And it was black. Not dark brown... black. I guess a really, really deep purple could be possible. But it looked black. And the cool, unmistakable characteristic, was a thin white ring around the "neck", about 1/4 to 1/2 inches from the mouth (anterior) end.

Anyone have any idea what this is?

Can't find it in my books, nor on the web. Thanks in advance. :-)
 
Of course a pic would help.
No doubt! If the opportunity arises I'll get one. But it is clearly VERY reclusive, or at least light shy. I may need to starve the tank for another 2 weeks to get it so show itself in dim light.

sounds like a peanut worm possibly
Thanks! I looked at a few pic of peanut worms, and this did not appear to look like them. Thanks for the help though!

Did it appear segmented?

If not, it might be some type of Nemertine (ribbon worm).
DING! DING! DING! Give that poster a prize...

It did not appear to be segmented - if you mean like a common earthworm. But with the black body contrasted against purple rock in dim light, the segments would be hard to see anyway. And BTW the body was "flat" black vs. a shiny or reflective surface, so indentations for segments would be a bit hard to seen. Just one more reason a picture would be nice...

But I looked up Nemertine, and found this post! And this one. So what I thought was a "collar", was in all likelihood a single ring of many, as shown in the first link.

In the 2nd link I don't like the description at all...
"In one group of nemertines is tipped with a piercing barb known as a stylet. In other nemertines, the proboscis is unarmed, but often secretes sticky fluid. Normally, this proboscis is retained in a specialized sac in the animal's body, the rhynchocoel. To capture prey, the proboscis is rapidly everted (turned inside-out) and shot out of the rhynchocoel. It wraps around the prey, and toxic secretions immobilize the prey; nemertines with stylets use them to stab the prey repeatedly, introducing toxins into the body."

I DO NOT want that sucker in my tank!

Thanks for the help!

I'm getting rid of that rock...
 
If it IS a nemertine, I would love to have it!

Most are not that dangerous.

Mine never hurt anything in spite of being nearly 4 feet long.
 

Attachments

  • Ribbonworm top.jpg
    Ribbonworm top.jpg
    61.6 KB · Views: 0
If it IS a nemertine, I would love to have it!
thanks for the post... And the pic! If you reduce the interval of the white rings (lose 2 out of every 3) that's exactly what this is. Check the first site I linked to above for a pic of these things with significant space between the white bands.

But your willingness to take this has me wondering... Have I lucked into a cool thing? I think we are all for as much bio-diversity that we can squeeze into our tanks. But that desire has limits. We don't want aptasia. Or flatworms. Or a number of other nasties.

This appears to fall into the class of "nasties". Why - on the back of your experience with a single individual of diverse species - whole you want another one of these animals?

Thanks for the posts! This is facinating. :-)
 
I love interesting and uncommon creatures.
Although some are reported to have the ability to capture small fish, I have never heard of anyone having a problem with one in a reef tank.
If it is a nasty, it can always live in a sump or spare tank.
 
I had one or two small ones that appeared to eat some zoos and LPS. I removed them and they seem fine. Not worth the chance in my eyes.
 
If it IS a nemertine, I would love to have it!
If you want it, and you are willing to make the drive up to Westport sometime soon, you are welcome to it. Gratis.

But you could not pay me enough for it to be worth my trouble to get styrofoam shipping boxes, and bags and such, and ship it. Shipping's a PITA.

So THANKS for the identification help! It's yours if you wanna come get it. Pls let me know. :)
 
Back
Top