snailid15

FAQs about Marine Snail Identification 15

Related Articles: Gastropods, Sea Slugs, Mollusks, Abalone,

Pyramid snails on Cerith Snails? 04/14/2008 Hello Guys, <Howzit?> I have a very successful, although unintentional, breeding program for Cerith snails in my aquarium. For the last couple of weeks I have seen another variety of snail riding along on many of them. They are small white snails that meet the description of a Pyramid snail, and sometimes a Cerith will be carting around two or three of them attached to the front portion of its shell. I have Zoanthids and a clam that are all untouched and in perfect health, no snails present. None of my corals have been touched in the least from what I can see so far. I also breed Checkerboard Nerites and they are not bothered by them. I understand that Pyramid snails are specific feeders, but are they this specific? Is it possible I am seeing something other than Pyramid snails? <Oh yes, of a certainty> I am not noticing an increase in snail deaths in my aquarium at this time, as judged by an increase in empty shells, but I have a couple of hundred Ceriths so a small change would be difficult to detect. It's hard to tell an occupied shell from an unoccupied one when there are so many of them. If these do turn out to be Pyramid Snails that are specific to my Cerith snails is there any way to get rid of them without harming the Ceriths? <Mmm, not easily... but some small snail-eating fishes (e.g. wrasses, see WWM re) might reduce and keep small snail numbers down...> Hand removal is impossible, there are far too many of them. Never mind, I already know the answer to that question :) I have a 6-line wrasse, and maybe he is picking them off the clam but can't get to the ones on the Ceriths, since they are primarily active after dark when the wrasse is asleep? <Maybe...> I have seen these snails climb the glass on occasion, but it's not where I would look for them first if I wanted to find one. If a picture is important to you it would be easy to obtain one, if I knew how to use the macro on my camera. I will figure it out if need be though, don't hesitate to ask. Thanks in advance, Barbra <If these small snails aren't causing direct trouble, I would ignore them... there are MANY gastropod species... Most are not predaceous. Bob Fenner>

What Are These Calcareous Discs On The Live Rock? ...Nerite Snail Egg Capsules 3/30/08 Hi Crew, <Hi Tom, Mich here.> Could you tell me what these small (1-2mm) gray/white discs are that are growing all over our live rock? <Yup.> They're flat, hard, round plates and can easily be popped off intact, not like the usual coralline algae I'm familiar with. <They are Nerite snail egg casings. You can read more about them here: http://www.advancedaquarist.com/issues/sept2003/invert.htm > The tank is about 130G and has been set up for 3+ years. Some of the rock has been in use 6+ years, some less than 2 years. We run a Chaeto fuge, calcium reactor, PhosBan reactor, EV180, 2x 250W Ushio 10K MH lamps (10hrs/day) w/T5 actinic/blue. Good circulation, over 4000GPH total from 2x SeaSwirls, 2x Koralia-type powerheads, and a chiller loop. We keep mostly SPS up high, a few small Euphyllids placed low, and a medium fish load. Water tests as follows: 80-81 deg F SPG 1.026 dKH 10.9 Ca 425 Mg 1320 NO2, NO3, NH3 are all consistently zero I scrubbed several rocks clean about 2 months ago but the discs are regrowing. Seems strange that they just started showing up about a year ago. They only grow on the live rock, while the walls and sides of the tank grow lots of pink, purple, and maroon coralline. I'd rather have the coralline cover the live rock...but mostly just these discs, alga, and a little Cyano seem to grow well on the rocks. <All very common.> Thanks, <Welcome! Mich> Tom

Re: What Are These Calcareous Discs On The Live Rock? ...Nerite Snail Egg -- 04/1/08 Capsules Thanks Mich, <Hi Tom> Let me provide a better description for you. I'm not sure these discs are egg casings, at least they're nothing like other snail eggs we've seen come and go. <No they are quite different than the gelatinous masses many other snails produce.> They look/feel like some kind of non-organic growth. <Yes, they feel very tough, almost calcium like.> They don't have the sesame seed shape of the Nerite egg capsules as described in the linked article. These discs are flatter, thin, and brittle...a tiny, plate-like, calcareous growth. Think of a miniature poker chip, but even thinner and with a sharp edge. They're evenly spread over all areas of the live rock...high, low, everywhere. They number in the thousands, not just tens or hundreds. <Yes. Your description/image appear to me to be consistent with Nerite eggs.> We have mostly Astraea, Nassarius, and Ceriths. We do have a few Nerites and Stomatellas that hitchhiked in, but not in large numbers. This morning I couldn't find any Nerites at all. Wish I could get a better picture for you. Do you still think these are produced by Nerites? <Yes I Tom
<Cheers, Mich>

Baby Snail Question. Hey, I'm not a baby, I'm a Collonista! 3/30/08 Good day WWM, <Hi Josie!> I am writing to get an opinion on a baby snail that I discovered in my tank this morning. <It's actually not a baby/juvenile, but rather a diminutive snail species usually referred to as a Collonista, or Mini-Turbo snail. They're harmless and beneficial herbivores/grazers that are mostly nocturnal, reproduce readily, stay small (usually around 3mm), and have a characteristic pit in their operculum (trap door at the opening of a snail). Color/pattern varies, with some being all white like yours, while others are combinations of white with varying amounts of mottled tan/brown/even pink markings.> Currently, as far as snails go, I only have Nassarius, Fighting Conch, and Margarita Snails and low and behold, I find a small, Â¼?white snail with 2 tentacles crawling on the glass this morning. I have done some searching and found that Margarita Snails do not typically breed in captivity; <Not successfully, no. In addition, they're unfortunately cooler water species that live shortened lives in reef systems.> ..however, the shape of this baby is nowhere near the same as either the Fighting Conch or the Nassarius Snails. <Very true.> I have not added anything new to my tank in about 3 or 4 months and the tank is over 1.5 years old now. <Because of their size and nocturnal nature, these little guys are often overlooked.> The shape is very similar to the Margarita. I have included a picture although it's not the greatest as it's difficult to take good pictures of the tank with the camera I have but it's the best I could do. <That's okay, I think we're good to go! For more information, please see the following links as well as WWM's search engine using the term 'Collonista': http://www.wetwebmedia.com/snailidf14.htm http://reefkeeping.com/issues/2004-05/rs/index.php http://www.wetwebmedia.com/WWMAdminSubWebIndex/question_page.htm > Again, thank you so much for all the great information on WWM as it's always my first stop for information! Josie <Mine too! Bob and the crew past and present have amassed a very impressive amount of information here, and it just keeps growing! Take care and enjoy those Collonistas, -Lynn>

Flatworm Or Nudibranch... Or Maybe Not... (Not) -- 03/28/08 Hello guys, <<Adam>> I have an interesting creature in my tank, I've read through the forums and search across the Internet and I cannot get a positive ID on it (Even checked the sea slug site you guys listed as a resource.). <Okay>> It resembles a Nudibranch, although the one picture I found of something that resembles it, you guys ID'd it as a flat worm. (http://www.wetwebmedia.com/fltwmid.htm, second picture from the top, question titled Nudibranch or Flatworm.) <<Mmm, not a good picture is it? Regardless 'what you have is NOT a flatworm>> Flat worms are generally not as large as this animal is, or at least I thought they weren't. <<Some do get large>> The guy is around 2 - 2.5" and only comes out at night, I have seen what seems to be "antennae" protruding from it. <<Yes>> I tried several different ways of taking the shot, one strictly with LED's, others with flashes and/or an LED flashlight. I have attached a few shots. <<I see them>> One peculiar thing I witnessed last night was a split in the animals back. <<Hee-hee! A clue!>> Down the center, which opened slightly and receded when I placed the light over him. Any ideas? <<Indeed 'see below>> I am at a loss and don't know whether to enjoy the little guy or eject him. I monitored him for about an hour the other night when I saw him open up down the middle and never really saw him feeding on anything and he stays around a rock in the tank with Zoanthids, and a piece of orange Monti. Only thing I could guess is filter feeding or feeding off the worms and such in/on the rock. Thanks again, Adam <<Well Adam, I've seen a couple of these before. What you have there is Scutus antipodes (Black Limpet, Elephant Snail, etc.). The 'split' you saw is where the mantel parted (the mantel comes up from both sides to cover the shell on the animals back). This critter is reputed by some to be reef safe...others to be a Cnidarian muncher'¦but all seem to agree it's a good algae grazer and a prolific breeder. Regards, EricR>>

Re: Yellowhead Jawfish... Horse Conch comp. Thank you for the answers! I have to apologize again for asking so many questions, I did find some more info and realized that some of them probably shouldn't have been asked. It is just so overwhelming when you have so many different questions and you are getting different impressions from different sources. <Focus... one thing... at a time> I will definitely look into reading those books. I still haven't bought the Jawfish, but he is still there so I have hope! I bought 20 lbs of live sand and some live rock, and I'm letting everything cycle. Hopefully all will be well before he is sold. I am also preparing myself to part with one of the crabs so I can free up some more tank space for him. There is one question that you didn't answer in my last email, and it was a pretty big concern of mine. Will the horse conch try to eat the Jawfish when he (the conch) gets to be a few inches long? <Shouldn't, no. Pleuroloca gigantea eats mainly other snails and bivalves> I have visions of the conch positioning himself over the jawfish's hole and sticking his body down there to eat him... the way he does with the snails he eats. I was able to get a better picture of the conch to send to you; he wasn't being very photogenic last time. I'll attach a picture of one of my Marginellas, too. Thank you again for your time and knowledge! :) <Welcome! BobF>

Marine Snail Identification: Likely Fighting Conch - 3/21/08 <Hi there, Steve> Thanks for the site. and on to my question. <Okay, let's get to it!> I've had a snail in my tank since I started it back in April of last year. I just had someone point out to me that they thought it was a tulip snail <Good news - it's not!> and that he would eat other inverts in the tank. <Nope, they're safe.> I browsed your Marine Snails FAQs and spotted something that sort of matches my guy but not 100%. Can you give me your thoughts from the photo?? <It looks to be a harmless/beneficial Strombid, likely Strombus alatus, aka the 'Fighting' Conch or similar. These are good sand stirrers and mainly herbivorous, but may also take meatier fare.> He has eye stalks and a large snout? that he pushes out whenever I see him above the sand bed. <That's very typical of Fighting Conchs. Sometimes all you'll see are just the two eye stalks protruding out of the sand!> He wasn't being helpful when I took the photo.. <Heheee! Isn't that annoying!> Most of the time he's digging around in the sand bed and will disappear for weeks at a time. <Also typical of Fighting Conchs.> If he is in fact a Tulip Snail I have never seen him going after other inverts. Is this something that will occur when he increases in size?? <Nope, this little guy won't go after your other invertebrates/fishes - even when he's not so little! Speaking of which, they get up to about 4" or so in length. These Strombids do, however, need lots of open areas of DSB to survive long term.> He doesn't climb the live rock or tank sides. Just stays in the sand. <Yep, again, that's typical for these. All in all, they're neat little snails. Please see the following sites for photos and more information http://www.wetwebmedia.com/gastroart2.htm http://www.gastropods.com/9/Shell_1329.html (Strombus alatus) http://www.pirx.com/gallery/mollusks > Love the site and thanks for you thoughts.. Steve
<You're most welcome! Take care, -Lynn>

Mystery Creature In My Reef? Scutus - 3/11/08 <Hi Aaron> I caught this guy in action last night and I've seen him from time to time. One time I observed him on the glass and his mouth parts look just like a snail's. <Heeee -- and for good reason! It *is* a snail/Gastropod!> What is he? <It appears to be a species of Scutus, aka a 'Shield Limpet', in the family Fissurellidae. This family also includes Keyhole and Slit Limpets. It also looks a bit like a Chiton, but the two antennae rule out that possibility.> Is he some type of Nudibranch? <No, although they're often mistaken as such.> Would he eat coral polyps? <It's possible. Scutus spp. are primarily herbivores, but reportedly may also feed on coral tissue.> Should I take him out of my reef? <It's up to you. I don't have any personal experience with these, but most people seem to love them. Apparently they can be very beneficial when it comes to grazing/removing algae.> I have a 75 gallon reef tank with tons of live rock, Zoas, mushrooms, leathers, and LPSs corals. <Heeeee! You can add Scutus to the list now as well!> I've tried some of the more fleshy LPSs corals like open brains and candy canes and they seemed to have their flesh devoured. <Yikes! Although I've read cautionary statements regarding Scutus and corals, I've yet to read any actual accounts of coral predation within home aquaria.> Other LPSs corals like frog spawns, torches, bubbles, and Galaxea do fine. Could this guy be the problem or is it more likely my flame angel? <Hmmmm. While I can't rule out the Scutus, based on their popularity with aquarists, it wouldn't be my first choice of suspects. I'd be more inclined to suspect the Flame Angel, possibly even a Tang, or one/several of the other usual 'picker' suspects (various crabs, shrimps, etc.)> The picture isn't the greatest, but it's the best I could get at night. <Understandable! The good news is that I think we're good to go. For more information/photos, please see the following links: http://www.seaslugforum.net/factsheet.cfm?base=scutus http://www.poppe-images.com/images/search_results.php?category=Shells&family=FISSURELLIDAE > Thanks for your help! <You're very welcome! Take care, -Lynn>
Aaron Chandler

Sundial snail babies? Hopefully harmless Collonista snails! 3/3/08 <Hi there.> I recently found a few sundial snails in my tank. <Yikes, hopefully not dining on your prized Zoanthids! Do you keep Zoanthids or were these just incidental hitchhikers? Sundials only eat Palythoa and Zoanthids, so unless you have those, they'll simply die out. If you do have/keep Zo's, definitely remove any Sundials you see.> I now have many tiny, tiny snails I think could be their babies. Are there any natural predators for these snails? <I don't know of any that prey exclusively on Heliacus/Sundials, but I'm sure there are other predators that include them in their diet. Unfortunately, it's always possible that the predator(s) could have a taste for more than just Sundials (as in other beneficial invertebrates)! Complicating matters is the fact that Heliacus are mostly nocturnal. They're able to hide very effectively within Zoanthid colonies during the day when snail eating fishes are active. Regarding those tiny snails, there's a chance that they might not be juvenile Sundials. There's another very common snail in the genus Collonista (aka 'mini Turbos') that has a similar appearance, but is a harmless herbivore/grazer. They're mostly nocturnal, reproduce readily, and stay small (usually around 3mm). Color/pattern varies, with some being all white, while others are combinations of white with varying amounts of mottled tan/brown/even pink markings. A sure fire way to differentiate Heliacus from Collonista is to grab a magnifying glass and take a close look at the operculums (the 'trap door' at the opening of a snail). Heliacus have conical/pagoda shaped operculums while Collonistas are relatively flat with a characteristic pit in the center. Basically, if it's pointed, it's a Sundial. If not, it's likely a harmless Collonista. I'm hoping that you have the latter! Please see the following links for comparison/more information: http://www.wetwebmedia.com/snailidf14.htm (Collonista snails) http://reefkeeping.com/issues/2004-05/rs/index.php (Collonista - operculum shown) http://www.wetwebmedia.com/snailidf13.htm (Heliacus - see pointed operculum in photos about halfway down the page) I've got my fingers crossed for you! Take care, -Lynn>

What a surprise...but what is it? Looks like snail eggs! 2/2/08 Hello WWW Crew, <Hi there, Pat.> Thanks for your site! I have learned a lot from reading your answers and articles. <Excellent!> Starting a reef tank has been one heck of a learning experience and even after ~2 years I am still finding new things in my own tank and I have no idea what they are! <Heheeee! Isn't it amazing the things that can crawl out of a rock!> It has led me to purchase a microscope to examine things in new detail, some pictures which I have included. <Neat! Opens up a whole new world, doesn't it!> My question is I found about a dozen egg sacks on the inside of the cover of my MJ. They are a little larger than a BB and have some white things eggs in each one and in this one it looks like they are alive and moving. The only opening in the MJ is the two small holes ~1/8", and the sacks are larger than the holes. Do you know what they are? I am thinking amphipod eggs. <Nope, not amphipod eggs. The females carry the fertilized eggs in a brood pouch until they're ready to hatch. What you have looks very much like snail eggs, but I'd love to know how they got there!> In the first picture there is a copepod in the upper right to give you an idea of size. <Thanks.> In the second, just below center is what I think is a partially developed pod. It is upright with a black eye and a clear antenna and darker body? <I see that. Looks like a developing embryo -- hard to tell what it is at this point. Please see this link for photos/more information: http://www.reefkeeping.com/issues/2003-02/rs/index.php.> I guess I can always wait and see if they develop more. <Yes please, and document as much as you can! I'd love to see the progression/development!> Both pictures are in the following link: http://cmas-md.org/forums/showthread.php?p=305826#post305826 Please feel free to download the pictures from the link to post, I have had problem with sending you e-mails with attachments. <Ok, thanks.> Thanks for your time, Pat
<You're very welcome! Take care. --Lynn>

Snail Identification: Likely Horse Conch - 2/2/08 Hi all, <Hi Jenn!> Just a quick thank you for all the information and first hand knowledge you provide to SW hobbyists! <You're very welcome! It's a pleasure!> I have searched your site for the answer to what type of snails we have in our 75 gallon reef tank. We bought them not long after we started our tank, a little over a year ago. They are pink bodied. They do not seem to be aggressive on algae or other waste. I am also including a few pictures of the snails for identification. <Thank you for sending multiple angles by the way, that really helps. Your snail looks like what's commonly called a Horse Conch, which is in the family: Fasciolariidae. The snails in this family are predatory towards other molluscs and will scavenge dead or dying organisms. Have you noticed any other snails missing? Horse conchs (likely yours is in the genus Pleuroploca/Triplofuscus) range in soft body color from orange to a dark red. Please see the snail at this link, just past halfway down (Florida Horse Conch) for comparison: http://h2ocreatures.com/mollusks.html .> We are looking to continue to build our reef with additional LR and also want to get a hardworking cleanup crew. Suggestions would be great. <Sorry, would need to know what other livestock you have, what type of clean-up you need.> Thanks for your help! Jenn H Central PA
<You're very welcome! Take care. --Lynn>

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