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FAQs about Marine Worms, Vermiform Animals Identification 9

Related FAQs: Worm IDs 1, Worm IDs 2, Worm IDs 3, Worm IDs 4, Worm IDs 5, Worm IDs 6, Worm IDs 7, Worm IDs 8, Worm IDs 10, Worm ID 11, Worm ID 12, Worm ID 13, Worm ID 14, Worm ID 15, Worm ID 16, Worm ID 17, Worm ID 18, See Also: Flatworm ID 1 +, Nemertean, Proboscis, Ribbon Worm ID 1, Nematode, Roundworm ID 1, Nematomorpha, Horsehair Worm ID 1, Acanthocephalans, Thorny-headed Worm ID 1, Tubeworm/Featherduster ID 1 +, Bristle Worm ID 1 +, Hirudineans, Leech ID 1, Sipunculids, Peanut Worm ID 1, Echiuran Worm ID 1, Invertebrate Identification, Worms 1, Worms 2Worms 3, Flatworms/Planaria, Fire/Bristleworms, FAQs on: Worm Behavior, Worm Compatibility, Worm Selection, Worm Systems, Worm Feeding, Worm Disease, Worm Reproduction,

Related Articles: Worms, Featherduster Worms

Gray marine worm and greenish marine worm... Shades of Ted Geisel!   4/27/07 Hello, <Howdy> I've notice two rather large marine worms in my 55 gallon aquarium I can identify. <?> I've searched through a few books I have, searched on keywords in Google and examined each of the photos on your webpage, and used your local search engine but can't fine anything that matches the two worms in my tank.  I'd really appreciate some help in identifying these worms, and if they are harmful to my aquarium.  My tank has been set up for about 15 months with 50 lbs of live rock and the recommended amount of live sand. Worm#1: I can only see about 1.5" of it.  It appears light green on top with a line of what almost looks like white cilia going down the length of the side of it.  It is about the side of an earthworm, and has very narrow segments.  It has built a tube made of sand which is about 6 inches long and rests on top of the sand.  I at first though it might have been a feature duster I have, but the feather duster has a light gray tube which looks kind of paper-like.  I have not seen the feather duster for a couple of days, so maybe it is possible.  This worm has not moved much in the last few days.  The part of the worm I can see might stretch out to about two inches or compress down to about an inch, but it doesn't do it at a speed which is noticeable. <Is likely a tubiculous polychaete... not all are "feathery"> Worm#2 This worm has wider segments, and is completely light gray.  I've see it (or a second one) sticking out about ¾ of an inch out of the sand.  In both cases it was right up against the base of a piece of liverock.  This worm moves it head around much more noticeably than worm #1, and appears to have a darker head-like area at its tip, almost like a caterpillar. This worm is also about the diameter of an earthworm. <Another polychaete... There are thousands of species... most are either innocuous or desirable... I would leave these be, unless they "bug you"... You can read re removal on WWM if so. Bob Fenner> Any help you can give me on identifying these worms and what I should do with them would greatly be appreciated. Thanks, Ken

Re: gray marine worm and greenish marine worm  - 05/02/07 Thank you very much for your response.  I not usually worried about the small creatures I find in the live rock, but after doing some research on your webpage and looking at the size of them I was a little concerned.   I'll leave the worms alone unless they become a nuisance or over breed.  They help to keep my sandbed stirred up. <Ah, yes... There are MANY species of worms in the oceans... Some places in very high population densities...fulfilling many important roles. Best to relax, enjoy them in our aquariums... unless too large, predaceous... BobF> Thanks again, Ken

Trayless Query with worms! Lynn to Adam J's Rescue... Vermiform animal comp.   4/9/07 Hi again, <Hi Wes...Adam J here again> I just sent you all a question about tang compatibility (Clown and Sohal) <I answered that one.> but I have a completely unrelated question for you. <Okay.> I just now noticed a creature in my tank (wanna say it's a worm, but it was in and out so quick). It stuck its head out (off-white in color), discharged a milky white substance into the water and stuck it's head back in. The whole thing happened in less than a second. It looked like if you were to inject about a thimbleful of milk into the water. I couldn't really believe it when I saw it. The substance seemed to dissipate in a matter of seconds. The hole it came out of was about an 1/8 to 3/16 of an inch in diameter. No picture to share, as it was over so quick. I know this isn't much info to go on, but any clue as to what this could have been? My tank's been up and running for about 6 months and this is the first time I've noticed anything of the sort. Should I be worried? Should I take the rock out of the tank? <Wes, as you know it is very difficult to take a blind swing at to what this animal is/was with verbal/written description alone. However we have a new-crewmember who is very adept in things like this and I went to her for input here it is: "Hmmm, my first guess would be something in there releasing gametes, whether it's a peanut worm or even possibly an embedded clam, etc. I wonder if there were any other clouds showing up around the tank at about the same time? That would confirm a spawning event for me although I guess it could have been just an isolated one.  I've seen similar things in my tank once or twice (in 4 yrs) and it honestly always happened so fast that I didn't' t get a chance to see what critter did it.  I would tend to believe it would be something like that though rather than poo. Seems like if it *was* waste...we'd all be seeing a lot more worms, etc, releasing those clouds rather than the occasional sighting. Anyway, that's my two cents.. hope it helps!" - Lynn Thanks, <Welcome... Wes Shive <Lynn....(mostly Lynn) and Adam J.>

Worm or what? Yep, spiral tube feather duster (Spirorbis spp.)   4/1/07 Hi guys: <Hi Roger, Mich here.> I started noticing some new critters (about 9 or so) on the glass of my 20-gallon marine tank.  I also have a 10 and a 55 gal.  I recently (week ago) bought a cleaner wrasse and moved him into the 20 gallon to make sure all was OK before moving him into the 55 gallon.  I also bought and introduced to the same 20 gallon a few crabs to help scour the bottom.  I'm attaching a picture of the critters on the glass though it's not real clear, <I'll say so!> hopefully you get the picture....no pun intended.   <Got it!> They are little half moons to spirals and less than a sixteenth of an inch.  Could you please identify for me? <Yes. You are correct, they are a type of worm, specifically, a spiral tube feather duster (Spirorbis spp.).  They are present in most marine systems.  They are harmless and feed on dissolved nutrients in the tank.  Some have brightly colored crowns of red or orange.  Enjoy!> Thanks.

Worm-like growth  ID sedentary snail (Petaloconchus spp.)  3/30/07 I have a hard worm-like structure growing out of my Pagoda coral as well as one growing out of the base of my torch coral. The thing seems to spew out this web-like substance that gets tangled around my rocks and structures. Any idea what this is? <Yes, sounds like a sedentary snail (Petaloconchus spp.)> Is it dangerous <Nope!> and how can I get rid of it? <I wouldn't.> Thanks. <Welcome!  -Mich>  

SW Worm ID  3/23/07 Hi,     Please ID the following: <Look like Bristle Worms to me.  Harmless unless they get very large.  Brandon.> Thanks,

ID this worm(?) please, and Medusoid     1/17/06 Dear Sir/Madam, <Will you read my book? Oh, sorry, not one of the Beatles here> I have my marine tank 29 gallon BioCube in the 5'th week of cycling. I also have about 28 lb of live rock and about 2 lb of live sand. This past weekend I've added an 11 snails and 6 red-legged hermits. Snails took a very good care of the algae on the rock... Everything seems to be looking perfect, until I found some kind of worm(?) on the inside glass eating the pods. <Mmm, yes... some sort of Platyhelminth...> I have an extremely high pods population: when I clean the glass inside, they will reappear within the same amounts in about 2-3 days. I'm attaching a picture with 2 critters one on the top is an unidentified one (length of about 3-4 cm) and the bottom the pod that is about to be eaten. This thing on the top moves really fast! I also noticed, that there are one that is splitting on the glass, that looks like there will be another two instead of one soon. It took that thing to split up about 5-6h. Thank you very much for your time and effort in maintaining such an excellent site. <Welcome... these are flatworms... I would just wait, let them pass on their own here (likely will in short order... no need to try and selectively poison...)> There are also something else that I noticed today...I turned off my powerhead, and noticed those little tiny thing (about 2-3cm), that move by pulsating. Looks like jellyfish. Are these ones good or bad ? <Mmm, could be bad... but likely will also go of their own accord... Are likely some sort of tissue-grade life (Cnidarian, Ctenophoran)... that are arising from a hard substrate...> Unfortunately I were not able to make a good picture of it, but it is on the 2'nd picture... <I see this... a Medusoid of some sort... you can read about such with a search of WWM, the Net... and the terms above.> Thank you very much for all your help...Regards, Andy Stavickis
<Welcome. Bob Fenner>

What the H, E, Double Hockey Sticks is This?   1/8/07 Hi! I was wondering what this is. it is slightly green in color, very flat, no shell, <That you can make out> around 2 inches long and almost as wide. Movement is similar to a snail, almost looks like some sort of Nudibranch. Cannot see eyes, mouth, etc. It's kinda trippy, little freaky!  I have been having problems with margarita and Astrea snails dying, don't know why. I found this creature simply draped over 2 margarita snails in the sand at night, trying to get at them. I think it was feeding on them but not sure. Do you guys know what it is? <Mmm, is it very flat, wavy at the edges? If so, might be a flatworm of some sort... If not, possibly a sea slug of many possibilities...> It is certainly out of my tank! It took some effort to capture, but I was successful. It is currently in a cup with pinhole size holes in it, in a net, in the sump! LOL! I had it in a sealed cup with bigger holes (approx.1/4 inch in diameter). Damn thing escaped within 3 minutes! captured it again. I am going to bring it to my LFS for identification tomorrow, but not sure if they can help. Attached to this e-mail is the best photo of it. Thank you! <Oh! Does appear to be a Platyhelminth to me. Bob Fenner>

Spiral free-swimming worm?   1/4/07 Hey there! <Hi there Ellen!  Mich here.> Last night, about an hour or two after I turned off the actinics, I noticed a strange "worm" in the water. It was about half an inch long, white/grey in color, and swam freely up towards the moon lights. <Many types of polychaete worms like this, are drawn to the moonlight, often as part of reproductive events.> It spiraled up towards the lights in the shape of a perfect corkscrew. <Interesting to watch, No?> <<And not harmful. RMF>> When I shone the flashlight on it, it curled up into a ball and sank down to the sand. <Yes...instant sunshine...a natural response.> Any idea what this might have been? <Yes, any of a number (big number...like in the hundreds or more) of different types of polychaete worms.>   Thanks for all your help! <Welcome!> Your forums are a constant source of information to me-Ellen <Good to here this Ellen.  Glad you have benefited from them.  -Mich> What Are These Worms?  12/15/06 Hi guys, I just want to say I've gotten addicted to saltwater reef tanks because of my friends who are huge tankers and your website has helped me a ton so thank you. <You're welcome.> Now for the question.  I just moved and bought a new 30 gallon saltwater reef tank which has now been set up for about 3 months with only about a dozen zebra crabs, about a dozen snails, a Zoanthid colony, and a small group of star polyps.  Anyways, I noticed a bunch of small Nudibranch looking worms crawling all over, and seemed to be eating my Zoanthid colony so I removed them with a small pipette. <Seemed to or did?> After removing them, I then noticed very small (about maybe 2 mm in length) white worms all over the stalks of the zoanthids.  What are these worms, and are they eating the coral or just eating algae or whatever else of the stalks?  If you could please help me out cuz I'm kinda nervous about this and don't want to lose any of my corals.  Thanks a ton guys. Justin <Justin, there are  gazillions of worms in the marine environment.  Without a picture clear enough to identify, it would be near impossible to give an accurate description of the worms in question.  If you have a camera with macro capability, take a few shots and resend.  Someone may then be able to identify the critters.  James (Salty Dog)>

Medusa/Spaghetti ID - 12/04/06 Greetings, <<Hello>> I wonder if I could bother you to ID this picture of what I think is a spaghetti worm. <<It does indeed look to be Loimia medusa, the Medusa or Spaghetti Worm>> Also, they are helpful scavengers??  Correct? <<Yes...a beneficial detritivore...as well as a favored food among some fishes>> I plan to put it back into the tank if that is advisable. <<Yes>> Thanks for your help yet again. Cathy
<<Happy to share.  EricR>>

Re: Medusa/Spaghetti ID - 12/06/06 Thanks so much for the ID. <<Quite welcome>> I had the strangest thing happen today.  I came home to spider webs (like things) all over my reef tonight!  Do you have any ideas about that? <<I do...these are likely the feeding filaments of Polychaete worms...probably from the family Terebellidae, like the Medusa worm you found. I did my usual Monday night water change.  Nothing else new thanks again for the ID. Cathy <<Mmm, try having a peek with a flashlight after dark...many new wonders to discover...  Eric Russell>>

What's that in your tank? A worm!  11/23/06 I recently noticed possibly a worm critter in my salt water tank. This surprise was seen coming out of a hole in the rock. It was hanging out about 1", trying to pick up a piece of raw shrimp. It looked like a worm, with Black Bands going around it. The end of it looked like a miniature Featherduster. As it was trying to pick up the shrimp it was acting as it were sucking on it while trying to pick it up . What sort of creature have I inherited?  Thanks, Revs <Hi Revs, Mich here.  Sounds like you inherited a Sipunculid or a peanut worm.  Think of it as part of the clean up crew.  Sipunculid worms are beneficial detritus feeder.  Hopefully it will establish it's species in your tank.>     

Electric worm in my reef tank! Now on a fateful cruise   11/22/06 My wife accidentally stumbled across this article on your website.  Fifteen years ago we had searched everywhere for information about  glowing blue saltwater worms.   <Neat> At that time we had been stranded in the gulf three miles north of Marathon in the Florida Keys.  Our boat propeller bushing had failed as we were returning just before dark from a snorkeling trip.  We switched to our small kicker motor to continue on. <Thank goodness you had the kicker> As darkness fell a violent thunderstorm moved over us with heavy rain, lightning and high waves swamped our  small kicker motor.  We dropped anchor and waited for the storm to pass. <Smart... and called on the radio...> After the violent storm the sky and sea were pitch black. The water was like glass but dozens of strange bright blue lights began to appear in the water within a hundred feet around our boat.  I called my family up on deck to see this amazing sight.  My youngest son said "Maybe this is what you see right after you die." <Cheerful> One of the lights was near the stern and I shined my spotlight on it.  It was a worm about two inches long that glowed a brilliant blue from end to end.  The water appeared to fizz with tiny bubbles around its' body and the worm looked like it was spinning at a high rate of speed. <Another good clue>    After about ten minutes they all switched off at once and were gone.  After a great deal of library searching and talking to other sailors in the area, only one had ever seen them before.  The article on your website is the first we've seen that sounds anything like what we saw in the ocean. <Yep... some species of Polychaete... likely an "epitoke"... reproductive unit/segment... clued by the tides, moon... possibly the storm... to surface, kick out the jams so to speak... Look up epitoke on your computer. Bob Fenner>

Is this an Orange Fire worm?  11/12/06 <As good a name... Yes>   I spotted about 3-4 of them behind my  filter box.  The largest one is about 1.5".  Are they harmless? <Mmm, to a degree... not fun to get poked with (watch your hands) and can/will eat animals in your tank...>   Cool pic huh?!  (2 photos attached) <Very nice> Lou Montanaro Toms River, NJ <Oh, was just by there last August. (Mum in law in Belmar). Bob Fenner>

Swimming Worm?  11/10/06 Hello crew, I have a 55g sw with 50lbs. of live rock, and several small marine fish and inverts. I was just looking to see if you folks could identify this little guy for me. I have enclosed a pic of this 1/2" worm, rear 2/3 is orange while the front third is white with two little beady black eyes. <Mmm, the pic didn't come through...> Caught it one night zipping through the water column at warp speed. I would have liked to leave it in there, but didn't know if it was parasitic or not. <Highly unlikely this is a parasite> Must have hitched a ride in on the live rock. I would like to know if you believe these little guys are ok to leave in there if any more pop up in the future.  Thanks,   Jose from Chicago. <Are fine... there are a myriad/cornucopia of species of worms and other organisms that are the live portion of LR... that are very largely beneficial to benign. I would not be worried here> P.S....great website, you've been a lot of help to a lot of people. Thanks again. <Ah, good. Bob Fenner>

Identifying a Worm 11/6/06 Hello All and thank you for your efforts in keeping us all informed. <Hi> It seems my hunt for the worm in question as been unsuccessful. So I turn to the You (WWM crew) for help in identifying and information as to it's possible diet. It appears to shrink inside itself as it retracts. Attached is a photo. Thank You Tom <Looks like a peanut worm, feeds on detritus and microscopic organisms.> <Chris>  

Parasite, no usable information 10/24/06 I noticed today a worm looking parasite on the front glass of our tank at work. It  has been there all day in the same spot. It's white and is about 2 inches long and 1/8 inch wide with its body folded perfectly back and forth like a paper fan. Does this sound like anything you've heard of before? Thanks for your help, Nancy <Need for information.  Fresh water, salt water?  Check out the articles on WetWeb for a possible picture.> <Chris>

Worm Identification - 10/18/06 Hi all!  <Hi Don, MacL here with you tonight.> I love this site. I must say though, there should be some kind of certificate available after so many hours of reading, ha, ha. <Tell me about it, five hours in the past two days reading, researching and trying to answer people's questions. I think people know when Bob Fenner is gone lol.> There is much to be learned here.  I have been cycling my tank for 2 weeks now. I have noticed a couple things I haven't seen before nor can I find anything like it.  The picture of the sand has a couple dark blue/grey spots, I am assuming this is associated with the denitrification process? <Definitely and its looking good.> The other two are of an alien that is living in my tank, seems to be a cross between a Nudibranch and a bristle worm. <Looks like a bristleworm to me.  Could be a Nudibranch but is much more in character with the bristleworm other than its color.> I was hoping for some clarification, plus I am sending pictures so that's always fun.  Thank you for your time.  P.S. What book is best for FOWLR people (but more interested in the LR part.)?   <Any book that is going to tell you about different types of invertebrates is going to help you. Personally the book that Bob Fenner and Anthony Calfo wrote about invertebrates has some great pictures that will help you immensely.  I believe there are connections from the website to take a look.  Good luck, MacL> Respectfully,
Don W. 

Worms from Newly Mixed Water?! 10/15/06 Hi Crew, I bought a bag of Reef Crystals salt about a month ago, and have already done a few small (weekly) water changes using it, after allowing the water to sit for about 2 days after mixing before adding it to the tank. Since that time, I've twice noticed a tiny little, extremely thin and long worm wiggling around on the live rock. I paid no real heed to this, thinking it was just a small bristle worm, which I've had in the past, and which have caused no problems (not Fireworms). My tank has now been in fallow mode for about 2 weeks, i.e. no fish, just lots of hermits, snails, feather dusters, mushrooms, and other inverts. About 2 weeks ago, I mixed a 5 gallon batch of water, using salt from this same bag of Reef Crystals, aerated it for awhile, and then covered it with a plastic bucket lid, and have just let it sit there ever since. I used distilled water, (as I always do), and the bucket has never been used for anything else. I always rinse the bucket thoroughly in scalding hot water after every use. Today I took the lid off, preparing to do another small water change and substrate vacuum, and found that there were a slew of little worms lying on the bottom of the bucket. They had to have come from the salt. There's no other explanation that I can see. I'm guessing they may have grown from dry eggs/spores or whatever from the salt, kinda like dry brine shrimp eggs do. <Sounds reasonable, except that Reef Crystals is a chemical mix made in a lab, not dried sea salt like the Red Sea brand... would be highly unusual for this to happen. Would contact Aquarium Systems about this.> I tried looking around your website and the web, looking for a similar story, but wasn't able to find anything, Maybe I'm just using the wrong search terms. <Or it's a unique story.> Anyway, here's a picture of one of the little critters, with a penny alongside for scale. <Without the penny, it looks suspiciously like a rubber band.> I wish I had a good microscope and the capability to photograph it with such, but I'm afraid I don't. The worm (it sure looks like a worm), appears to be flat as opposed to cylindrical in shape. Please tell me this isn't a parasite, or something else harmful! <Have seen worms like this before, mostly on the bottom of well established tanks, and often quite long (over a foot). Hard to be more specific when dealing with the most diverse group of animals on the planet - could be a parasite, then again could not - 50/50 chance. I'm willing to take a bet and say they're safe. Still, would contact Aquarium Systems and be prepared to send Dr. Tim one of these worms in a jar.> Thanks,
Rick G.
<Cheers, J -- >
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