CnidIDF12

FAQs on Identification of Stinging-Celled Animals 12

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

Can You Identify This Please'¦ Hydroids -- 03/08/08 Hello <Hi there, Mich here.> I have a 125-gallon marine tank that has been up for about 6 months - this is my third tank. Can you please tell me what the small brown things are - I believe that they are either a cluster of tiny glass anemone (I haven't been able to find any pictures on the web of tiny clustered glass anemones but did read on WetWebMedia that they do come very small) <Nope.> or some sort of tiny cluster feather dusters. <They are hydroids, perhaps Myrionema sp. They can be a nuisance and you will need to wear gloves when removing them as they can deliver a sting. They seem to be about 1/4 inch long each. Let me know if the photo is not good enough and I will get a friend with a better camera to take a picture. They are so little it is actually difficult to see the details of them. <The picture is fine. There also appear to be worm snails (Petaloconchus spp) in the background, which are harmless filter feeders, but be careful when moving about them as they can be quite sharp and easily puncture finger tips.> I do know what a normal glass anemone looks like and have had them before but never this tiny. I did read on the site that the fish will avoid them and I have not seen any fish stung but they do seem to avoid them. If these are glass anemones I will try to remove them, <Hydroids are pests and should be removed.> my biggest problem will be that they are on one of the rocks my feather duster is attached to, which is reasonably close to one of my bubble tip anemones. Can you suggest the best way to remove these without damaging the feather duster or the bubble tip anemone assuming it is tiny glass anemones. <Well removal can be a bit of a challenge. If possible, you should remove the rock from the system while you go about with the removal of these buggers so they are not accidentally spread. You will likely have to remove the top layer of the rock, as much as an inch with a chisel or Dremel as these pests can attach themselves quite deeply in the rock.> thanks for your help and for this wonderful resource. <I am happy to help and I too thank all who have contributed to this tremendous body of work. I was a student here before I was a teacher.> regards Jackie for NZ <Cheers, Mich from the good ole US of A.>

Tiny pest anemone or some type of polyp? (Picture Included) 3/3/08 Hello WWM crew, I would first like to say, your site is a treasure trove of information. Now back on topic, I've noticed lately on one of my live rock there are about 2 dozen of these tiny things. They look like polyp, with over 24 tentacles, white brownish in color, retracts a little when touched, and about a few millimeters in height. I've been digging through your website trying to figure out what they are, and I was hoping there might be a picture, but I haven't seen one or probably missed it. So far base on other peoples description, it sound like Aiptasia, right? <Mmm, not necessarily... could be Zoanthids, other types of Polypoid life... Even just juvenile forms... Likely transient... will go in time> I've included a picture which has a pair of them near the upper center of the photo. Thanks, Kent <I see them... but need more detail than these show. You can work your way through the description of the major Cnidarian groups here: http://wetwebmedia.com/cnidaria.htm Thanks for sending this along. Bob Fenner>

ID please -02/29/08 Please see attached. I can't tell what it is, but hopefully someone can. :) <I'll try!> Grows very tree like and on top of a colony of some palys. The 'polyps' withdraws into itself and tips becomes a whitish color (like the ones up the top of the picture). When they're open, they resemble zoas/palys, with a green center. http://ericdo.com/pictures/Starfire%207.2.07/unknown_soft_022708.jpg <Wow, that's certainly something different. Is there any chance you could get a close up of the open and closed polyps?> Please let me know if you guys can ID it. <To be honest, I'm not even entirely sure it's even a coral... but maybe some type of hydroid? More pictures will help.> Many thanks, Eric <Best, Sara M.>

ID please -hydroids 02/29/08 <Eric- Just following up... I asked one of my friends who is more of a marine invert ID expert and he agrees with my guess that it's a hydroid of some sort. But more importantly, he was able to explain a bit of why he thinks so. The tubes are brown and translucent which suggests they're proteinaceous, not calcium carbonate. That means it's not a coral. And neither of us can think of anything else (except a hydroid) that would have branching proteinaceous tubes (and have polyps) like this thing has. Hydroids are extremely difficult to ID, but if I can narrow it down more at all, I'll let you know. :-) Best,
Sara M.>

Outstanding. RMF.

Need Help With An ID No One Knows In My Reef Forum 2/24/08 <Hi Jim, Mich here.> I bought snails from the LFS and on 1 of the shells was this aiptasia looking thing, that's what I assumed until it released itself and started swimming. It swims like a octopus flailing its tentacles I've posted on a reef forum and looked all over the Internet researching this thing but have come up with nothing. Any help would be appreciated. <Looks like a hydroid jellyfish to me. More here: http://www.ronshimek.com/Animal%20Groups%203%20Cnidarians.htm http://www.wetwebmedia.com/jellyidfaqs.htm > I do have it in a catch bucket but was wondering if it's safe to put it in my reef. <Likely wouldn't hurt. Populations tend to wax and wane. Is interesting to observer for sure.> Thank you for any help you can give me. <Hope this helps. Mich>
Jim

Identification question 2/23/08 Hi you guys have great info here. I was curious if there was anyone there who can ID these things in my tank. <Mmm, are Corallimorphs. Please read here: http://wetwebmedia.com/corallim.htm and the linked files above> They look like some sort of mushroom. Several have come off the rock they were initially growing on. Where they had been attached has a hard stony reminder. The ones that have come off are living happily on the bottom of my tank. These can blow up to quite a large size, 5-6 inches across and 1.5 inches "tall", or expel their water and get down to being just 1-1.5 inches across and maybe 1/4 inch tall when fully compressed. One pic is taken under actinic lighting and the other is under white light. <Very nice. Thanks for sharing. Bob Fenner>

These are actually anthocauli, i.e. baby Fungia -Sara M.

LR Critter ID 2/18/08 Hi all, Thanks for putting together such a great site. I can spend hour upon hour sifting through all the great data. The wife is threatening to limit my time on WWM. <I have recently "found" your message delinquently here... Will respond> I need help identifying this little critter that hitchhiked in on some live rock (see attached photo. Its not the best quality. It's harder than I thought to get a nice clean picture). Its about a quarter of an inch tall by 3/16 diameter cream colored stalk topped with a group of white/translucent balls at the end. <Yes... some sort of polypoid, Cnidarian animal> Its growing in a shaded area of the rock. Originally, this little guy hung around about a month after I cured the rock then receded to barely visible nub. I figured that it was a critter that couldn't survive in the tank and didn't think about it much. However, it has now grown, receded back a nub and grown back again 3 more times over the last 5 months. Since it seems rather tenacious, I would like to see if I can provide better for its needs. Any ideas or pointers to it's identity would be greatly appreciated? Thanks in advance. Dave <Might be an anemone... perhaps a Zoanthid... to some degree photosynthetic maybe... Please read here: http://wetwebmedia.com/cnididfaqs.htm and the linked files above and where you find them in text... till you find enough information to satisfy you. Bob Fenner>

Help with ID please 2/8/08 Hiya....Its Andrew by the way...from here on WWM... <Hello Andrew. Nice to see you from "the other side"> Would it be possible for anybody to ID the pointed out in the attached picture please...A friend has asked myself, and I do not know...learning time for me I guess... Thanks ladies and gents.. Andrew <Mmm... interesting. My best guess is that this may be a sea pen of some sort... does the "head" ever open up? If so, would you have an image, close-up of this sent along? Cheers, Bob Fenner>

Ricordea under a rock ledge... Maybe Majanos 2/5/08 Hi All, I love your website! I have learned so much from it along with the book "The Conscientious Marine Aquarist". <Hello and thanks! Bob's book is great isn't it?!> I recently acquired a 55 gallon reef tank set up with LR and LS. It was covered with green hair algae that has now died off (amazing what decent water will do). OMG the things that are now appearing on the rocks! I have discovered 3 Ricordea under a ledge of the biggest rock and completely in shadow about 2-3 inches above the substrate. Will they move to seek the light or should I try to move them? If I need to move them, how should I go about doing it? Due to the angle, I can't get a chisel in there to get them on a chunk of rock. Thanks so much in advance. These are very pretty bright green little guys I really want to help out. Peg <Peg, Ricordea don't usually just pop out on rocks. However, Majano Anemones do. Here is some FAQ's... http://www.wetwebmedia.com/anemoniafaqs.htm These types of anemones pack a big sting and are not very well liked by aquarist as they sting and kill corals. Google "Majano Anemone Pics" and see if they are the same ones you have. HTH, Rich...aka...Mr. Firemouth>

Re: Ricordea under a rock ledge 2/8/08 Thanks, Rich (Mr. Firemouth? Surely there's a story to that alias) <I love to breed Firemouth Cichlids.> I've read all areas on your website and looked at pictures on the web. It doesn't look like any I've seen: no pedicle, lies flat and no bubble tips. Still it must be a Majano of some sort. I just got a Ricordea Yuma and they sure look alike in structure. <It could be possible that it is a juvenile Rhodactis Mushroom Coral from the Tonga area. They would have the Yuma Ricordea appearance/structures.> I'm going to go with Anthony's response to "Pest Anemone" on 2/14/03, pretend they're not a pest and try to keep the pretty little guys from multiplying. <To help prevent rapid spreading of a pest anemone while keeping it in the system, you can take the rock it is on and make an island away from the main liverock structure. These anemones spread in close proximity of each other and can be concentrated on one rock by keeping the rock isolated. Many times these majano type anemones tear their "foot" while moving and create a new anemone. This is known as petal laceration. Another thing they do is divide. They "split" into 2 separate pieces. Therefore, it is much harder for them to spread all over if they are isolated. A picture of the anemone would help. Good luck and happy reefing!-Rich> Thanks again, Peg

Re: Ricordea under a rock ledge 2-14-08 Hi, I'm sorry for the delay in responding. I did not have much (OK any) success with my attempts to photograph the "thing". I finally found a picture on the web and it looks just like mine, it is labeled as a green Ricordea. I dug out my dive camera, but need new batteries. I will keep trying. Thanks again, Peg <After reviewing the pic provided it does look like Ricordea floridae. Here is a link with more info... http://www.wetwebmedia.com/corallim.htm <<Image not placed as it is others property. RMF>>

ID help, please 2/5/08 Hey Crew, <Andy> Presently curing a batch of live rock pending setting up my tank in March, and came across these on a small piece of rubble; not a great picture, I know, but any thoughts you might have are much appreciated. IÂ¹ve searched all of the sponge and anemone ID pages, and IÂ¹m not having any luck. I donÂ¹t THINK theyÂ¹re Aiptasia, but IÂ¹m a relatively new to the hobby havenÂ¹t seen all of the variants of that pest. What do you think, friend or foe? Thanks, Andy <The larger batch of stalked polyps at top? Please see here: http://wetwebmedia.com/zoidfaq2.htm and the linked files above. Bob Fenner>

Re: ID help, please 2/5/08 Thanks, Bob. Yeah, they do resemble the Palythoa, with one row of 6-8 tentacles. I thought I read that the Zoas are toxic, <Are, to many organisms... including humans> but my hermit crab seemed to enjoy them as a snack... twice. Looks like they're easy to care for, as well. I'll keep looking to see if I can classify them more accurately. Thanks! Andy
<A closer-up pic please. BobF>

Re: ID help, please 2/5/08 Bob (or crew), <Andy> HereÂ¹s a little better picture, not much, but such are the limitations of my little digital camera. This is certainly a truer color. A friend suggested these might be Green Star Polyps. <Does appear to be a Clavulariid> Thanks again,
Andy
<BobF>

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