There's something really creepy in my rock

[Anonymous]

Hello all.
Newbie here to the reefkeeping world. My hubby and I have successfully had a fish only tank for about a year and a half and have recently started a reef tank. The live rock has been in the tank for about a month now, and there are some funky things starting to make themselves known.
One little creature kind of disturbs me. There is a small hole in one piece of live rock, from which protrude a number of very thin and very, very long brown and white striped arms. These arms are smaller than the width of a human hair, yet stretch several inches. It's very active, whatever it is, and occassionally shoots out copious amounts of sand and gunk from its hole. Could someone please tell me what the heck that thing is? I've done lots of searches online using the above description, and in the course of my research have identified many other things that have hitchhiked their way into our tank, but I've not seen anything remotely resembling the description I've provided.

Many thanks!

Sherri J.
"Cakepro"

 

[Anonymous]

My first guess would be a brittle starfish

 

[Anonymous]

Spagetti worm possibly?

 

[Anonymous]

Well, I was unable to count how many arms there are...I am estimating that there are 8 or more. I just got a digital camera this morning, though, so give me a day or so on capturing and uploading an image of this thing. It kind of reminds me of an octopus of all things, but whatever kind of body that is radiating those arms is well hidden in the hole in the rock. It is able to bring back bits of sand and stuff into the hole -- not through retracting its arms, but rather by contractions along the length of the arms bringing material down into the hole. It doesn't appear that the arms get thicker promiximally.

Sherri J.
"Cakepro"

 

[Anonymous]

Cakepro,
Another Houstonian! I just moved here...

Since there are so many arms, I am thinking it is a worm of some sort, probably in the group known as terebellids (or commonly as spaghetti worms as Guy wrote). Brittlestars would only show perhaps 4 (5 at most) arms, and they should get a bit thicker toward the mouth. These spaghetti worms can have many sticky tentacles and spread them over the rocks, pretty far from the hole, looking for bits of food. I think that is what you've got! They are good at picking up stray bits of food.

Here is a site with some pictures of a big relative of your hitchhiker! (I think they look much better stuck in the rocks!): http://scilib.ucsd.edu/sio/nsf/fguide/annelida3.html

Have fun with the camera!
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Brittlestars! http://home.att.net/~ophiuroid
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[This message has been edited by ophiuroid (edited 25 April 2001).]

 

[Anonymous]

I think that's it! And woooo, you are correct in stating they look better stuck in the rock -- heh heh. Thanks, guys, for helping me ID that thing. I'm a little leery of unknowns...I'd hate to have a blue ringed octupus hiding in the rock unidentified! :-D

Ophie, have you heard of the MARSH club? It stands for the Marine and Reef Aquarium Society of Houston. Check it out: www.marshreef.org. The next meeting will be on Monday, May 7th, but I've not yet heard where or what the topic will be. My husband and I joined just last month and have met some great people. There are tank tours of members' homes and summer collecting excursions in Galveston...fun stuff!

Sherri J.
"Cakepro"

 

[Anonymous]

Hey Cakepro,
Hadn't heard of that organization. I'll have to join because I am interested in learning more about the hobby. I don't have a full scale tank but would love one someday. I am simply a little old marine invertebrate taxonomist who loves trying to figure out what these little obscure critters are (especially if they are brittlestars!). I am considering finding a job at an aquarium shop (the market for marine invertebrate taxonomists being a bit limited). I am AMAZED by all of the shops around here! FISH everything and anything!!! Quite a wonderful place this is!

Hopefully we will meet at a MARSH gathering soon! Thanks for that info!
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Brittlestars! http://home.att.net/~ophiuroid
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[Anonymous]

Well, if you need any practice before applying at any local stores, you have an open invitation to come over and identify all the nifty stuff growing in and on our live rock!

The hyperlink I posted earlier accidentally has a period at the end...the link is www.marshreef.org

Sherri J.
"Cakepro"

 

[Anonymous]

I think it might be a worm of some sort, if the arms are so thin yet a few inches long. Are they the same width the whole length, or do they get progressively thicker near the hole? How many arms stick out? Two or Three or many more? Any chance you can get a picture?

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Brittlestars! http://home.att.net/~ophiuroid
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