Anyone Know what this is

Posted this thread to the top critter ID person--a friend of mine from WWM. Here's what she said:

Unfortunately, I can't see enough of the critter to be able to tell exactly what it is. If possible, it would be great to see a shot of it in a bowl, completely under water. In the current photo, the worm/polychaete appears to be in a container with just a surrounding bit of clinging water, which can cause all sorts of visual distortions. What's particularly important to see in detail is the head and at least a couple of "legs". Small differences in both areas can make all the difference when it comes to a basic ID (usually at the family level). Beyond that, it can require a scope to study the various parts - especially the head/mouth -jaws. As an added bonus, there are periods (juvenile and/or reproductive) during which a given polychaete can look completely different than the more familiar, commonly seen/recognized stage.

Offhand, I'm thinking that it's probably something in the order Phyllodocida. Those big, obvious eyes (large to gigantic in size compared to the head) are typical of the family Alciopidae. Species are small, somewhat transparent and do occur in tropical waters, but the family as a whole is described as pelagic, not benthic. I didn't see anything mentioned about where the subject was caught - in the water column or rockwork/substrate, but it would be worth knowing. These worms are carnivorous, apparenly preying on pelagic tunicates and small crustaceans - copepods and the like. Unfortunately, I'm not a polychaete expert. There are many variabilities here and many genera in the order (if I've even got the right one!). Who you need is a Polychaete expert like Leslie Harris who has done an awful lot to help hobbyists online with their various ID's.

In the meantime, here are some examples:
Alciopidae: http://www.naturamediterraneo.com/forum/foto.asp?TOPIC_ID=67735
http://1.bp.blogspot.com/-7rxueg9K5YY/UDTcYZqAI0I/AAAAAAAAABM/HgbDmUbKHEY/s1600/alciopidae.JPG

Phyllodocid: http://eol.org/pages/463597/overview
Phyllodocid (with pharynx extended): http://www.flickr.com/photos/artour_a/5193379240/

Here's a good site for basic anatomical info:
Phyllodocidae: http://www.nhm.ac.uk/research-curation/research/projects/taxinfo/browse/family/phyllodocidae.htm
More info on Alciopidae: http://researchdata.museum.vic.gov.au/polychaetes/Alciopidae/description.htm
 
I'd like to thank everyone for their info.Im leanig towards the alciopiade. I'm just hoping these don't get into my trachipyllia brains. And eat them from the inside out.will be keeping a close watch on the tank.
 
Hi everyone! I was contacted by Jeni regarding the critter here in question and am glad that I was able to help. Even if it's not an alciopid, at least we have something to compare it to! Anyway, I'm glad to have joined this forum and am looking forward to some fun in the future!
Take care,
-Lynn
 
Lynn Z said:
Hi everyone! I was contacted by Jeni regarding the critter here in question and am glad that I was able to help. Even if it's not an alciopid, at least we have something to compare it to! Anyway, I'm glad to have joined this forum and am looking forward to some fun in the future!
Take care,
-Lynn
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I think Jenni has referenced your expertise in the past as well. We appreciate the sciency stuff!! Welcome to Chicago Reefs!
 
Thanks Herbie, I appreciate the warm welcome! Guess I'd better go post something in the intro section!!
 
I actually thought about it - then vetoed it for the turtle we saw on vacation a long time ago!

By the way, something occurred to me regarding the worm-like critter. It could be something like an epitoke, a reproductive stage where a polychaete transforms its body from a benthic crawler to a swimming form that enables it up swim up into the water column and spawn. They can be pretty different/freaky-looking, including having more prominent eyes, and segments that in some, break off and swim away or release gametes etc. Here are a couple of links for examples:
http://wetpixel.com/forums/index.php?showtopic=9847
http://depts.washington.edu/fhl/zoo432/plankton/plannelida/pl_annelida.htm
Here's one from my tank (a 4" nereid epitoke):
View attachment 11985
View attachment 11986
 
Well, some polychaete eyes can and do change (typically enlarge) when they go into their reproductive phase, but as far as changing color, I honestly don't know. The one I had (a mature nereid epitoke - pictured above) would have died after spawning (I removed it from the tank before that happened). Basically, the worm morphs into a swimming form, ascends into the water column along with a bunch of other worms and literally ruptures, releasing gametes, and dies.
Different Polychaetes reproduce in different ways. The coolest, I think, are the ones that bud - especially a syllid called Myrianida pachycera. Where nereids end their lives with a spawn (like Pacific salmon), syllids live to spawn another day. They bud and jeez can it be bizarre. Myrianida pachycera, in particular, reminds me of a kiddie train ride at an amusement park. That is, it has a big engine at the front that pulls many little cars behind it. In this case, the segments range in size and maturity from smallest/least mature towards the head, to largest/most mature at the distal end/"caboose". Once the last in the chain is "ready", it separates and begins its life. The rest follow suit until all are detached, then the main/adult section goes back to its regular life.
Here's a link with a photo of this species at the top, and a more thorough explanation of different reproductive processes:
http://coo.fieldofscience.com/2009/05/my-genitals-just-grew-eyes-and-swam.html
 
That has got to be the strangest means of reproduction that I have heard of... and that article is awesome. That Syllis ramosa is truly bizarre... amazing to see the different forms that life takes!
 
That Syllis ramosa is truly bizarre... amazing to see the different forms that life takes!
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Isn't that the truth! S. ramosa is definitely out there. I just want to know how the heck it moves around in one of those deep sea sponges when there are so many heads? Two-headed snakes tend to have a dominant one but what happens when there are many? What if one has consumed everything within its reach, and wants to move away (or into another sponge channel), but you've got a host of others already feeding that are trying to veto the move! I can only guess that maybe it's an all for one and one for all situation? Either that or maybe the sponge's recovery/repair rate is quicker than the rate at which its consumed. It's definitely a bizarre situation - a lifetime of "Hey, cut that out, I'm eating!", or "Oh no, another head just sprouted out of my back". Makes me glad I'm human!
 
Lynn Z said:
It's definitely a bizarre situation - a lifetime of "Hey, cut that out, I'm eating!", or "Oh no, another head just sprouted out of my back". Makes me glad I'm human!
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Haha, too true! I wonder if it still retains a dominant head, or if it takes on some type of hive mentality? (Or maybe they all just assigned a day, lol) Would be curious to get a better understanding of its nervous system!
 
I do come to think of it! Last I recall you said you had colonies of geiger aliens? Any still up for grabs? :)
 
Pufferpunk said:
I gig, I don't think it's either. Teeth? What teeth? I almost never remove anything from my system. 99% of what you see are good guys. I did see a blue-eyed black-clawed crab yesterday & broke my beautiful orange monti in 1/2 trying to get it out & they it scooted away. :(
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hey can i have the crab if you catch em?
 
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