CnidIDFAQs6

FAQs on Identification of Stinging-Celled Animals 6

Related Articles: Cnidarians, Water Flow, How Much is Enough,

Aiptasia, or something else? Something else: Hydroids! 10/11/07 Hi! <hi there!> I've been reading your site for about 6 months now and it has been wonderfully helpful in identifying and learning to care for all the creatures in my aquarium. <Terrific!> There is one I haven't been able to identify, however. They grow in clusters and have long, skinny brown stalks (about Â½ inch long). <Uh oh> There are around 10 or 12 tentacles which are very fine and wave constantly in the water. <Yep> I have seen Aiptasia in my tank and have removed it, but these look different. Can you identify these and please tell me if they are good or bad? <I'm sorry to say that they're hydroids and they are definitely bad.> I pulled about 50 of them off the rock yesterday with tongs and then remembered your admonition about pulling Aiptasias off of rock. I hope I haven't caused these to multiply horribly! <Although such removal is a very bad thing to do with Aiptasia, the same is not true with hydroids. The best method is to manually remove them at the base with tweezers. Just be sure not to touch them as you might get a nasty sting! Please see these links (and related blue highlighted links at the top) for more info re: http://www.wetwebmedia.com/hyzoancompfaq.htm http://www.wetwebmedia.com/hyzoanidfaq2.htm Good luck. I wish I could have given you better news! Take care --Lynn>

Creature ID'¦ Pseudocorynactis sp, Aiptasia 10/3/07 Hi, <Hello Ben! Sorry for the delay. I had some problem accessing your links> great site. <Thanks.> We purchased a beautiful 11 lb live rock from our dealer, upon which are all manner of things - feather dusters, anemones, plant life, a small clam, a huge pulsing xanthia, <Is pulsing Xenia, not xanthia, I noticed you spelled it consistently on your website, so I know it's not a typo, but wanted to give you the correct name for these fascinating creatures.> just a cornucopia of living goodness. <Amazing, isn't it?> We popped it in our 55-gallon tank, which was about two months old at the time, and everything has done just fine. <Glad to hear! Is this the tank in your bathroom? Is quite a beautiful bathroom I might add!> We've seen some migration (perhaps I should say spreading... not sure anything has actually left the new rock) of greenery, and generally are extremely pleased with how things are going. <Glad to hear! But do watch out with this Xenia... it can become a "weed".> We only have a couple of small, innocuous fish at this point, going slowly. <Slowly is good!> Parakeets in the mine, as it were. <Yikes... a Police song comes to mind here!> Gratuitous photo of rock and largest resident: xanthia here, on top of the rock: http://www.flickr.com/photos/fyngyrz/1454679708/ <I had problems with these links.> After a couple of days, looking closely at this rock, I noticed three widely separated (6 inches) flat, mostly elliptical deposits of what seemed to be jelly; they were all about .7 by .5 inches. On top of the jelly a bunch of short tentacles were evident, distinct enough from the main mass that they moved in the current whereas the main mass did not evidence any movement at all. But they were quite short. Here's a patch of the jelly+tentacles: http://www.flickr.com/photos/fyngyrz/1465601566/ <This appears to be Pseudocorynactis sp, a corallimorph.> (Not the same patch, the other two had already changed.) They kept up this appearance, not visibly changing, growing or responding to light or fish feedings for about two weeks. Then two of the three patches of [???] contracted to about .2", and grew sort of an onion-like shell half way up their sides. The next day, the shell completely contained them, and was almost closed, with a single point of white at the top. Now they've been that way for about three days, and the single dot has disappeared. <This may be an Aiptasia that has collapsed upon its self... a good thing... more reading for you below on this matter.> The last patch of jelly still looks the same as shown in the image above. Here's how a closed one looks: <This pic is a duplicate of the Xenia.> [???] here: http://www.flickr.com/photos/fyngyrz/1454679708/ <I think you mean this pic: http://www.flickr.com/photos/fyngyrz/1464688963/in/set-72157601955489783 > (Isn't that a beautiful rock?) <Ummm, if you like Aiptasia... You will want to try to eliminate this pest. More here: http://www.wetwebmedia.com/marine/inverts/cnidaria/anthozoa/Aiptasia/aiptasia.htm http://www.wetwebmedia.com/ca/cav1i3/aiptasia_impressions/aiptaisia_impressions.htm > I've not found a description of these on the net or your site, or this behavior, though I have tried repeatedly. Any ideas? <Yep... See above!> Regards,
<And to you Ben, Mich>
Ben

Another Anemone ID... Corallimorph? 1/19/07 I've been doing a lot of reading on your site trying to identify my new anemone, and not sure I can identify it without a little help. I sure appreciate having someone around who can take bad pictures and tell us what kind of sea creature we have found. More than anything trying to get the right mix of conditions for the animal to thrive is the mission. Here it is: http://i4.photobucket.com/albums/y138/dsmith14/IMG_0841.jpg http://i4.photobucket.com/albums/y138/dsmith14/IMG_0840.jpg I thought it may actually be a less common E. quad as pictured here in your article- http://www.wetwebmedia.com/Cnidarians/Anthozoans/AnemonePIX/Entacmaea/A._cla rkii_E._quad_FJ_LL.jpg someone else thought maybe Stichodactyla helianthus http://www.wetwebmedia.com/Cnidarians/Anthozoans/AnemonePIX/Stichodactyla/St ichodactyla_helianthus_StT.jpg The base has a very deep green color and it is very fluorescent especially under moonlights. the tentacles themselves are a light purple color with a deep purple dot at the end. Any help in getting a positive ID on this guy would very much appreciated! I do hope it is not a dyed Sebae as I at one time suspected.... D. <Please read here: http://www.wetwebmedia.com/mushroomidfaqs.htm Bob Fenner>

ID Help! Mystery Anemone (I think!), and a mystery coral = Pseudocorynactis caribbeorum and Briareum Hi - <Hello Stuart, Mich here today.> I just happened to be looking at my aquarium after the lights had gone off and noticed a new life form growing... It appears to be some type of anemone, but is not like some of the others I have seen... They are nearly completely translucent, with a barely visible almost iridescent green tinge. The only part that is not translucent are small bulbs on the tips. It is nocturnal, and immediately (almost violently) retracts if light is shone upon it (even if introduced slowly via flashlight), and is not visible during the day. It does have a visible mouth. Alas, due to its placement, I can't get a direct photo head-on, but did attach one with it's bulb tips showing. I can't believe that a bubble-tipped anemone would have hitch-hiked onto the original live rock, so needless to say I am at a loss as to what type of anemone this is. <I suspect this is a Pseudocorynactis caribbeorum. They typically extend their tentacles to feed at night, but with time may also appear during the day. Can be referenced in Aquarium Corals by Eric Borneman on page 198. Does it look like this: http://images.google.com/imgres?imgurl=http://www.deepseaimages.com/dsilibrary/data/660/5orangeballcorallimorph-jeuwcccco2002-001.jpg&imgrefurl=http://www.deepseaimages.com/dsilibrary/showphoto.php%3Fphoto%3D476&h=480&w=640&sz=60&hl=en&start=4&tbnid=ayaoNv5txFH6DM:&tbnh=103&tbnw=137&prev=/images%3Fq%3Dpseudocorynactis%2Bcaribbeorum%26svnum%3D10%26hl%3Den%26lr%3D%26safe%3Doff%26sa%3DG Another mystery life form that has been growing appears to be some type of slow-growing (although it has tripled in size!) encrusting coral which I have also been unable to ID on my own. It came in on the live rock and survived the cycling (I let the tank "season" for about 6 months before introducing any life aside from the live rock, did a fish-less cycle, let everything stabilize, cure the "cured" live rock, etc.) and this survived that process and has continued to grow over the two years since... Whatever it is, it must have been a tough one to survive the initial 6 months when everything was cycling & stabilizing. This appears to be a Briareum, an encrusting gorgonian. They are quite hardy and will tend to encrust whatever is nearby. Please take this into consideration with regard to potential neighbors. I've attached two photos. Thank you for all of your fantastic help and advice. This web site is by far the definitive aquatic resource, in print and on the Internet. <Thank you for your most kind words.> Very truly yours,
Stuart
<Hope this helps, -Mich>

Need ID on anemone? 1/8/07 Hello! <Hey Heather, JustinN with you tonight> I'm new to the web site, I love it! I have read everything related to the question I have and can't seem to find it. My question is this, I bought a few pieces of frag rock not knowing exactly what they were, now I have something growing and I have no clue of what it could be, can you help ID it for me? The growth is very pretty, its a pinkish pearly color, that branches up about an inch and have bubbles with skinny tentacles on the ends, at night when I turn the light off it goes down in to this purple blob like state. it almost looks like a bubble tip anemone, but the tips seem to skinny, but its still growing .. I probably have the worse light for anything like this to be growing but surprisingly its doing very well. I have a 1 strip light with a power Glo. I have a 1 year old fish only 29g with a lawnmower blenny, 1 emerald crab, 2 hermits, and 2 new juvenile ocellaris clowns, water conditions are great. Thank You! Heather, KY <Sounds like you have some sort of stinging-celled hitchhiker on your hands, Heather! Very cool! However, without a picture, an identification is very difficult. If you have the means, shoot a small picture or two of the creature back to us, we'll see if we can't help you out more specifically! -JustinN> <<Mmm, pinkish, bulbous tentacles... size, low light... Likely a Corallimorpharian... like a Corynactis species. RMF>>

Aiptasia?? Reading, following instructions? 1/6/07 Hey guys, I have had my aquarium setup now for 11 months, and for the last 4-5 months I have noticed an increasing amount of these white "things" they resemble Aiptasia, but much smaller than the typical Aiptasia I have seen they are maybe 3mm from base to top, not counting "tentacles". I would estimate I have maybe 1000 or more of these in my 30gal they have never seemed to bother anything, but I was curious as to what they were. I have included a picture, despite its blurriness I was hoping you might be able to decipher what it might be. Thanks, and sorry for the poor quality picture, but I don't have a very good digital camera. Thanks Again, Jason <Your graphic is too large... see our guidelines... and blurry for useful ID... but these are likely either some sort of Zoanthid, or Hydrozoan... better, smaller, more highly resolved images, please. BobF>

Aiptasia or what? 12/29/06 Here are some pictures of what the previous owner of the tank calls Aiptasia. I say they are Polyps or Zoanthids of some sort. Please help me end this debate. <Blurry Zoanthids for sure. BobF> Thanks.

Coral ID 12/9/06 The coral is branched type and has tiny spines covering the entire thing. It is soft to the touch. It was a hitchhiker from rock imported from the Caribbean. The coral started as a little clump and has grown into a large branch structure. I cannot find anything that is similar to it besides the Dendronephthya, but it is still far from looking like any of those species. Any help that would point me in the right direction would be great. Thanks for your time, Aaron <Hello Aaron, Mich with you tonight.> My guess from the photo is you may have a gorgonian colony / sea fan of some sort. A good hitchhiker. They are common in the Caribbean, and seems to fit your description and photo. Hope that helps! -Mich>

Aiptasia? - 12/04/06 Good day to you, and thanks for your service. <<Hello and you're welcome>> Like many others before me, I only learned of the risks of Aiptasia from perusing your website looking for info on my Macrodactyla purchase. <<I see>> On a piece of LR from my local supplier, I have noticed a fairly quickly growing critter; about 5 mm long stem with about 3 mm wide head. Concerned for Aiptasia as this appears to be the only one visible at present and might be readily easily eradicated. <<Indeed>> Before I drop Kalkwasser on it, can you confirm the identity? <<I can try>> See attached, heavily blown up and somewhat blurry photo. This was the best of several shots through my aquarium glass. <<Mmm, very difficult to discern from this photo. It could be a species of Palythoa, but with the elongated stalk and rapid growth I'm inclined to say yes, this is Aiptasia>> If this is Aiptasia, can I safely remove the LR into the air long enough to hit it with calcium carbonate slurry without harming associated button polyps? <<You can>> Thank you. Gary Holmes
<<Quite welcome. Eric Russell>>

Little clear/white thingies... 11/30/06 Hey folks'¦ <Greetings to you! Mich here.> I've been reading your FAQs about live rock hitch hikers until my head ached, and have not been able to identify this little critter --although it did help me identify some feather dusters that had me amused for a while! <Very good!> I have only been running my tank for a few weeks -- 55 gallon, with about 40 pounds of Vanuatu live rock (cured at the LFS). Since my cleaning crew started scooting around eating the algae, my live rock has been showing signs of life. <It is exciting, isn't it? Enjoy the magic that comes out of the live rock.> ;) The thing(s) in question are small, about Â½' tentacle looking things that are clear with little white tips. Sometimes I'll watch it for a few minutes and it doesn't move much (just with the current) and then other times I'll look and it's completely gone (withdrawn into whateverhole it's coming out of). I've attached a picture'¦ It's a little blurry, but I think that it shows the critter well enough. <A head on photo would be more helpful.> There appears to be 3 or 4 of these little things around the same area, but the one in the picture is most apparent. Any idea what I'm dealing with here? <Kind of hard to tell from the angle. If there is no skeleton visible it could be an invasive pest, such as Aiptasia, which you would want to get out of your tank. On the other hand it could be a friendly coral and nice addition to your reef. Its' behavior is similar to Aiptasia, but the white tips make me think it is not a pest. I'm sorry for the vague answer. I guess the best thing I could say to you is if you have four polyps this week and forty next week I would be concerned.> Thanks!
Kevin

Need Help with <sic> Coral Identification 11/19/06 Dear WWM Crew, <Joseph> Hi, got a piece of Fiji live rock with an unidentified hitchhiker. Attached is a photo. It looks like it could be an encrusting stony. <Mmm, count the number of tentacles/polyp... looks like an octocoral to me... not a hex, not a scleractinian> It is light pink with small white polyps. I have a 29 gal with 130w compact fluos. Will it survive on this amount? Thank you for your time. -Joe <... Seems to be surviving, growing... Looks to me to be a Clavulariid of some sort... poss. an encrusting gorgonian. Bob Fenner>

Creatures on glass / ID? 11/14/06 I came in this morning to find a handful of these tiny star-like creatures on my glass. I found somewhere in the FAQ that this might be foraminiferans, <Mmm, not Forams> but any photos I find don't match. Please see attached. Thanks for the great website! Jason Smith <Some sort of polypoid animal... might be a Hydrozoan... some other Cnidarian. Bob Fenner>

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