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FAQs on Identification of Stinging-Celled Animals 17

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

Related FAQs: Cnidarian IDs 1, Cnidarian IDs 2, Cnidarian IDs 3, Cnidarians ID 4, Cnidarians ID 5, Cnidarians ID 6, Cnidarian ID 7, Cnidarian ID 8, Cnidarian ID 9, Cnidarian ID 10, Cnidarian ID 11, Cnidarian ID 12, Cnidarian ID 13, Cnidarian ID 14, Cnidarian ID 15, Cnidarian ID 16, Cnidarian ID 18, Cnidarian ID 19, Cnidarian ID 20, Cnidarian ID 21, Cnidarian ID 22, Cnidarian ID 23, Cnidarian ID 24, Cnidarian ID 26, Cnidarian ID 27, Cnidarian ID 28, Cnidarian ID 28,  Cnidarian ID 29, Cnidarian ID 30, Cnidarian ID 31, & Anemone ID 1, Aiptasia ID 1, Stony Coral ID 1, Mushroom Identification, Soft Coral ID, Alcyoniid ID, Xeniid ID,

Unknown Coral Species Possibly Invertebrate? (Hee-hee'¦aren't they all?) -- 04/20/09
I'm sort of embarrassed to ask a question about a species identification, especially with so much information available over the net, at the LFS or the library. But in all honesty, I have Googled for hours and have stopped in every fish store to ask questions and still have no answers. (didn't make it to the Library)
I bought what I thought was a Xenia in one of the many stores that I frequent, I bought it thinking that I was well read and knowledgeable enough to take care of a new addition to my tank.
I picked out what I wanted, a light brown healthy looking Xenia with tentacles that started at the foot that was buried in the sand, and extended up about 3 inches.
<<Not a Xenia then'¦are 'encrusting' organisms>>
The shape is like a Christmas tree,
<<And this is your first clue>>
full at the bottom, gradually becoming smaller at the top. I walked away from the specimen tank to defend a poor little clown fish that was being picked on by bigger bullies and did not observe the employees putting my prize of the day in the plastic container, so imagine my surprise when I get home and see this brown looking morel mushroom looking thing suspended in saltwater.
<<A good analogy>>
(pick morels in woods every spring) Where's the waving tentacles and the little fingers at the end of the tentacles? So I fight the urge to drive back to the store, 50 miles away, plus the store was closed for the evening and I removed the brown wilting looking mushroom thing from the bag and have no clue what to do with it because it has a soft foot with nothing attached to weigh it down or prop it up.
<<Yup'¦another clue>>
First time I have had to deal with this, I always get coral that are attached to frag or rock. So I bury the foot in the sand,
<<A good move'¦>>
until the little bugger is somewhat upright. An hour or so later the tentacles start to creep out of the cap, woo hoo!!, the fish store people didn't switch a slimy mushroom for my Xenia. I turned off the tank light and went to bed. Next morning, I come downstairs and go straight to my tank and my poor half Shroom and Xenia are gone.
<<Clue number three'¦>>
Nothing there, vanished. I start on the morning tank regimen and come back an hour later to turn the skimmer back on and low and behold there is my Xenia waving around in the current.
<<A good sign>>
Now I am just dying to know how my Houdini Xenia just disappears and reappears, so I check the tank every hour or so and about 8 hours later, he starts shrinking, pulls all his tentacles so far into that funny little mushroom cap that you wouldn't even know that he had tentacles and he just got smaller and smaller, burying himself in the sand, until he disappeared.
<<Ah yes'¦>>
Next morning he pops up right against the tank wall, about 3 inches away from where he buried himself. I sort of push him a couple of inches away from the wall
<<Mmm, careful'¦best to let this critter pick its own spot>>
and he happily waved his Houdini arms and fingers around for another 8 hours and disappears. Next morning he pops back up against the tank wall, where he is currently residing.
What do I have?
<<The description and behavior you describe sounds very much like a Sphaerella or Studeriotes species of soft coral (http://www.wetwebmedia.com/paralcyoniidae.htm )'¦some common names are Christmas Tree Coral, and Medusa Coral>>
I cannot find any information on Xenia's that retract their tentacles and bury themselves in the sand.
<<Is not a Xeniid>>
I can't find any information about an invertebrate with tentacles like a Xenia.
<<Try a Google search on the Latin and common names I listed and see what you think>>
All the fish store employees just look at me funny and think that I am a twit who shouldn't be within 10 feet of an aquarium.
<<But, they don't know what this coral is either'¦right? >>
Do I care for it like a Xenia?
<<Mmm, no'¦this is an azooxanthellate coral that requires direct supplemental feeding'¦and much like Dendronephthya species, is not easy to keep. To be honest, I don't give you good odds for maintaining this animal for long as it will likely starve to death in a few weeks to months. You can try feeding small meaty foods like Cyclops-Eeze, Rotifers, etc'¦but in my experiences these animals always slowly shrivel away and die. I think the best thing would be to return this coral to the LFS for a refund/store credit>>
Houdini seems to be doing okay for now, but I'm concerned that it will decline in the future if I am not treating it accordingly to its species.
<<Even so'¦there's not a lot of info on the 'successful' care of this genus>>
I will try to send photos of his tricks, it's just a matter of catching him doing them.
Thank You for any information at all.
<<Sorry it's not better info'¦ EricR>>

Re: Unknown Coral Species Possibly Invertebrate? (Hee-hee'¦aren't they all?) -- 04/20/09
Hi Eric,
<<Hiya Beth>>
Thank you so much for the quick response.
<<Quite welcome>>
I apologize for the ignorance.
<<No worries my friend'¦you're smarter than you were yesterday, eh? [grin]>>
I really did research Xenia's but I guess, I am not knowledgeable enough to pick them out in a line-up.
<<An honest mistake, I'm sure>>
I live outside of Cincinnati and bought the coral in Dayton and although I could probably trade it or get my money back, do I really want to give Houdini back to a store that sold him as a Xenia in the first place?
<<Mmm, well'¦one of the best things we can do is to educate ourselves/others not to purchase such animals'¦or to return them when done after-the-fact. If the store can't sell it, then hopefully they won't order it in next time>>
Personally, I would rather lose the money as lesson learned and give him to someone who is equipped and knowledgeable enough to take care of him.
<<A fine sentiment'¦but what about the next time, and the next time, and the next time'¦?>>
(let me know if you know of someone)
<<Unfortunately there are few folks willing or able to devote to and maintain the specialized setup necessary>>
I included a picture of Houdini and I briefly researched both Studeriotes and Sphaerella as well as Medusa and Christmas tree corals. I haven't been able to find a photo that looks like mine but the described behaviors are on the nose.
<<Ah yes! It is now clear that what you have here is a species of Cavernularia'¦likely C. obese. Commonly called Sea Pen (though there are several similar genera/species also referred to re)>>
If you believe that it is not a Studeriotes or Sphaerella, then I'll try to take some photos of his disappearing antics later this evening.
<<Not necessary'¦am certain this is a Cavernularia based on your earlier description and these photos. And the prognosis may not be as dire as earlier perceived. Many species of Sea Pen are nocturnal and azooxanthellate as described in our earlier exchange'¦the fact that this specimen comes out when the lights are on is a good indicator that it is a photosynthetic species>>
If you want, you can tell me that I wasn't a knuckle head for thinking that it was a Xenia. Or you can tell me how you really feel and call me a raving Hulk sized knuckle head.
<<Mmm, not at all'¦ There 'is' a remarkable resemblance'¦especially to the uninitiated>>
Just a note, the folks at the fish stores had no idea what it was, one guy said that it could be a wild anemone and then showed me Aiptasia.
<<(sigh)'¦ Sad indeed'¦>>
Also, please do not think poorly of my tank upkeep.
I have been gone for the last two weeks to take care of sick relatives.
<<Sorry to hear>>
I have only been home twice these last two weeks, I tell my boys that I missed them and that is why I made the over 200 mile drive back home, but I really just want to check on my aquarium to make sure that everything is still alive.
<<Hee-hee'¦I'll never tell!>
This time I had a red algae bloom. The boys had been leaving the light on for too long, which is better than the last time when they hadn't turned the protein skimmer on for almost a week.
<<Hmm, sounds like a lighting timer is in order (your tank really would appreciate the regularity)'¦and maybe someone from the local aquarium club to check in once in awhile (if a possibility)>>
I have to leave again for another week and am terrified about what I'll find when I come home again.
Crossing my fingers and praying that they take care of the tank.
Thank you so much for your help.
<<Always welcome'¦safe travels. Eric Russell>>

Hitchhiker ID: No picture, but probably a Zoanthid by the description. 4/14/2009
I apologize for how vague this question may be but that's actually why I'm turning to you.
<Well, we try...:-) >
We have a 55 gallon corner aquarium roughly 2 months old.
<Welcome to the hobby.>
We have added around 30lb of varied live rock, a shallow 2 inch sand bed, around 20 snails (Nerite, Cerith, margarita and Stomatella), 2 peppermint shrimp and 1 diamond watchman goby. These are all of our clean up crew.
All water param.s are normal: 78 degrees, 0 nitrites, 0 nitrates, 0 phosphates, 400 calcium.
<Sounds good so far.>
We have a slight hair algae issue which may be contributing to our nice param.s but doesn't appear out of control and we're trying to starve it out with good quality water and slightly reducing the lighting.
<I'm one of the few who will say as long as it is controlled, it can actually be rather attractive.>
Now the question. As a brand new hobbyist I watch every inch of the rock obsessively to find new and interesting things as soon as they pop up. Or so I thought... Today at the top portion of one of the live rocks I found what looks like a little mushroom patch/grove. I reached in an gently felt it and each cap feels soft but firm. Most of the caps (I don't know what else to call them) are brown with 1 of the largest (and slightly offset...1/4 inch or so) is a medium to bright orange.
<Difficult to say with any certainty without a picture, but based upon your description, I would hazard a guess that they are Zoanthids.>
I've tried search for 'mushroom' and only get mushroom coral. I've tried search on hitch hikers and obviously get a wide range of snails, crab, worms and so forth. I don't know what else to do to narrow my search down. Have you heard of anything like this or do you have any ideas how I might better search for it? I've tried taking pictures but (probably due to the intense curve of the tank) I can't seem to get anything clear.
<The macro setting on your camera (usually depicted by a single flower) is best, do not use a flash, and indirect lighting - a flashlight works well.>
Any help would be appreciated and again my apologies for the vagueness.
<Do check the following pages, I've listed them in order of likelihood based upon your description.
http://www.wetwebmedia.com/zoanthid.htm and
http://www.wetwebmedia.com/corallim.htm >

Re: Newbie Question 04/05/09
Okay, I got some pics, but they are the greatest, I had a flash light in one hand and the camera in the other! Please let me know if this is aiptasia so if it is I can get it out of my tank. It is still only coming out at night. All of the tentacles have about 4 stripes on them, brown and translucent.
<Well, they don't look like aiptasia... but are possibly majano anemones (another kind of pest anemone). But it's hard to say for sure... I hope BobF or Lynn will comment if they have another opinion.>
<<Doe look like Anemonia... but only out at night? Is there a stony skeleton/corallite visible? RMF>>
Sara M.>

Re: Newbie Question, Cnid. ID 4/7/09
That was supposed to be aren't the best, so much for a 5am email! Okay, I will leave them for now and watch, I will update you if anything changes or if I can get better pics!
<Good idea, as BobF noted... it is odd that they only come out at night... and suggests that it might be some kind of coral. We'll see I guess...>
And my levels have dropped back to 0!
Thanks again for all your help and dedication to the site!! It is great and has helped me so much!!
<De nada,
Sara M.>

Aiptasia? Please Tell Me It Isn't So! -- 03/22/09
Hi there.
I hope everyone there is having a great weekend so far.
<<Can only speak for myself but yes, not so bad>>
I absolutely love WWM and have found it extremely helpful.
<<Ahh'¦is redeeming to know>>
I was looking in my tank tonight and noticed these creatures. The first thing that popped into my head was ahhh no is this the dreaded aiptasia?
<<Hmm'¦looking at the picture, I'm not sure>>
I just started my tank about 5 weeks or so ago and have been working on getting the stuff together slowly. I only have around 20 lbs. of live rock that I purchased from my LFS. There are around 5 or 6 of these on the rock so far. I looked at as many pictures as I could in the archives and in books. From what I have seen there are tons of different aiptasia "types" and couldn't find the exact picture of mine.
<<The photo provided is not really close enough or sharp enough for me to tell for sure. These 'could' be Aiptasia but I don't think so. They could also be Anemonia Majano, or a Hydroid; which some folks consider to be a worse scourge than Aiptasia (try some keyword searches on those names and see what you think). But to me, these polyps look to be Scleractinian rather than Actinarian (hard corals vs. anemones/similar animals) as it appears there is a 'skeletal structure' surrounding each (or maybe it's just the photo). I'll ask Bob to comment re if he sees this>>
<Mmm, is a Scleractinian... perhaps solitary Caryophylliid... I'd leave alone.RMF>
I was sort of hoping it would be something else like possibly some sort of worm?
<<Not a worm'¦but quite possibly a 'desirable' hitchhiker>>
I fear I am wrong though and wanted an expert opinion.
<<I can't be sure without a better resolved close-up photo>>
I thought I had taken precautions against these pests.
<<These may not be the 'pest' you fear'¦though it is essentially impossible to keep Aiptasia from eventually showing up in a system, in my opinion. Best to be vigilant'¦and to have a plan>>
I have 3 peppermint shrimp, and some red legged hermits, apparently mine don't eat these so hopefully it will be ok?
<<I have always found such 'biological controls' for Aiptasia to be unreliable and of little use. For Aiptasia/pest anemone control I very much recommend the use of Red Sea's Aiptasia-X>>
I have read emerald crabs eat these too.
<<Not in my experience>>
Maybe I'll be buying one of those?
<<The money will be better spent on the Aiptasia-X>>
I planned on changing my CC substrate to a DSB in the morning but now am unsure of what to do. I read a lot of posts where people get these epidemics and can't seem to get rid of them.
<<Based on the photo, you hardly have an epidemic>>
Should I remove the rock and let everything die off and never buy rock from this LFS again?
<<Mmm, no'¦a bit drastic and unnecessary in my opinion>>
Please tell me it isn't aiptasia.
<<Can't say for sure. Get a bottle of the Aiptasia-X and if they continue to spread or if it just makes you feel better, you can get rid of them. Otherwise, I would be inclined to watch/enjoy them for a while and see what develops>>
Thank you very much for your time and help.
<<Quite welcome>>
I don't have any friends in this hobby yet and don't trust the guys at my LFS after selling me the CC substrate and now this ugh.
<<The local fish stores (or anyone for that matter) don't always have all the right answers or provide the 'best' advice'¦and don't forget they also need to make a buck. Some stores are certainly better than others, but regardless of which is available to you; do your research ahead of time and learn to rely upon yourself and your own good judgment>>
Thanks again.
<<Regards, EricR>>

Nitrate And Unidentified Invertebrate 3/9/09
The picture isn't Jordan's award :>
I have two questions, I have a 65 gallon saltwater tank with soft corals and fish. I've had it for about 14 months and really enjoy it, although it is a continuous learning process. Water is changed weekly, calcium, strontium, and iodine was added and everything has been fine except I can't get my nitrate lower than 20.
<How about magnesium levels, is a major element.>
I've done multiple water changes, watch how I feed and everything is healthy in the tank. Is 20 an acceptable level?
<If your kit measures NO3-N, 20ppm would be acceptable for fish only systems, but for corals, your measured level is high.
Are you using a protein skimmer? This will aid immensely in lowering nitrate levels and is considered a must have for maintaining healthy systems.>
I've also got a new addition that must have come from the rock. Can you help identify it, I just want to make sure it isn't a glass anemone. The body is round with what looks like the mouth in the centre, the tentacles are long and fine like hairs.
<Picture is a little blurry but from what I can determine, it appears to be the dreaded aiptasia anemone. This needs to go.
Do search our site for info regarding this unwanted hitchhiker.>
Thank you for your help.
<You're welcome. James (Salty Dog)>

Coral ID 3/9/09
Hi there ladies and gents!!
As always, thanks so much for the great site and all the info. I don't know what I would do without you guys sometimes!
Like now. I could really use some help! I recently bought a critter pack, and need some ID help.
<? and ??>
I feel I need to give you a little bit of back-story, so you don't think you're dealing with an idiot buying mystery critters from random dudes. The owner of the company I bought from was very accommodating, letting me know he could adjust the critter pack to my needs. I told him what I have currently, so he could use his judgment on what would be most beneficial for me. He told me he was putting together something he thought would suit my tank, and that he'd email me what he was sending when he sent it. Which he did not do. And still has not done. The sale went great, but for the last 3 weeks I have not been able to get a response from him.?
Most of what I got was part of the original pack, I know what I'm dealing with.?There were some mystery stars which your wonderful site has helped me ID (Asterina).?But he included 2?coral frags that I'm clueless about.?I have searched through your site and through what feels like ALL of the internet, trying to find pics of them. I'm sorry to have to bother you guys, I know you must get about a billion ID requests. Although they seem to be doing fine,? I'm worried that since I have no idea what they are, I'm going to kill them because I'm somehow not caring for them properly.?I don't know what kind of lighting, food, flow, etc. that they need.
<Like the Judea-Christian book of mythos and other similar works, best to start off with naming, descriptive terms in common...>
? Let me start off apologizing for the blurry pics. I spent 20 minutes taking shots and that's the best I could get. My camera is apparently not as good as I thought!! Maybe a description in conjunction with my blurry pics will help.
? The pink polyps, I think they might be star polyps?
<You do have some Clavulariids here>
I've seen pics that are close, but nothing that looks exactly like them.
Some of them have 7 arms,? most of them have 8. They have what looks like bumps on the ends of the arms, that are colored green.
<Yes... GSPs for short>
Not sure if they are actually bumps, or if it just looks like it due to the color difference. The reason I'm not sure about the star polyp thing is because they are not feathery at all. The arms are very tube like. And they don't seem to be as long as in most of the pictures I've seen.
? The white fragment. This thing is crazy. I had to put a shade over it to take it's picture because the skeleton is so white it just kept coming out a big white blob in the pics. Very white skeleton, with very large nodes.
The polyps that come out of it are lime/fluorescent green. The only pics I have found that look similar to them are sun corals, but even those aren't right. Especially the colors.
<I do think you're on the right track here... There appears to be a Dendrophylliid in your mix of images>
? Both of these retract at night and come out in the day. They retract when touched, but do so slowly.?To get a size idea, both of the fragments are roughly?2 inches square. Maybe an inch & a half.?
? Thanks so much for your time!?I appreciate anything you can tell me to get me pointed in the right direction to find info on these things. Have a great day!
<Vic... you'd do well to either "check out" a coral book (Borneman, Calfo, Sprung, Fossa & Nilsen...) from a library... or pick up copies for your personal use. Bob Fenner>

Creature ID 3/5/09
Let me begin by congratulating you on a phenomenal website.
<Thank you.>
I'm just starting off in the world of marine fish keeping and your resources and advice are peerless. Thank you.
I have a hitchhiker on one of my pieces of Live Rock and I've searched your site and most other places on the web, but can't find anything that resembles it. The organism doesn't look anything like the images of Aiptasia or Anemonia majano that I could find, nor does it look like anything else that I've seen. Any help in IDing the creature would be
greatly appreciated. The centres of the organisms are a much brighter green that what shows up in the images. The tentacles retract very quickly into the body when disturbed and the organism seems to be flourishing and growing rather quickly in my otherwise barren tank (It's still just cycling with LS and LR)
<What you have is a small Zoanthid colony. Read here and related articles/FAQ's
Thank you again for your tireless efforts.
<Again, you're welcome. James (Salty Dog)>

Coral ID help 2/18/09
<Hi Gabriel, Minh at your service.>
Hello crew. Just need a little help with a coral I can't identify. I got this piece from my LFS when I purchased a few other things and they put this in there by mistake. I've been doing a lot of reading and looking at pictures and still can't figure out what this type of coral is. It has been in my tank for over a few months and seems to be receding. The
branches on it where longer and more defined at one time. This coral glows bright fluorescent green under actinic lighting. Any help you could give me in identifying this coral so I can research how to better care for it would be a great help.
<Based on the picture you've sent, it appears to be a Nephtheid. If you browse through this page, you can identify which genus it best resembled when it was healthy: http://www.wetwebmedia.com/nephtheids.htm. Care and
husbandry information is available in those pages as well.>
Thanks, Gabriel
<You're welcome. Cheers, Minh Huynh.>

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