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FAQs about Sea Slugs, the Opisthobranchs, Identification 2

Related Articles: Sea Slugs, Nudibranchs,

Related FAQs: Seaslug Identification 1, Seaslug ID 3, Seaslug ID 4, Seaslug ID , Seaslugs 1, Seaslugs 2, & FAQs on: Seaslug Behavior, Seaslug Compatibility, Seaslug Selection, Seaslug Systems, Seaslug Feeding, Seaslug Disease, Seaslug Reproduction, & Marine Snails 1Marine Snails 2Marine Snails 3 Nudibranchs, Nudibranchs 2, Nudibranch Identification, Nudibranch Behavior, Nudibranch Compatibility, Nudibranch Selection, Nudibranch Systems, Nudibranch Feeding, Nudibranch Disease, Nudibranch Reproduction, Berghia Nudibranchs, Snail ID 1, Snail ID 2, Snail ID 3

Help ID Tank Spaghetti  11/14/08 Dear Crew, <Hello Andy.> It's been a long time since I rapped at you. I've been out of the loop because my tank crashed in September and I haven't had much to write about <Sorry to hear about that.> -my only inhabitants are a Kole Tang, a Sea Hare (Aplysia californica) that I borrowed from my LFS to deal with the incredible amount of algae that plagued my tank after the crash from (I assume) all the nutrients that were released when $3k worth of fish and coral disintegrated, and a bunch of hermits and snails. I know this Sea Hare is a temperate water species and will eventually starve in my tank, which is why I borrowed it rather than purchased it--I needed something big to eat an incredible amount of algae. Anyway, as I mentioned there is very little in my tank--I am letting my tank settle/re-mature and don't want to load it up with any fish for a few months. Almost nothing survived the crash, so almost all life other than the above is new that came in on a few new pieces of LR and some bristleworms, etc. that I transferred from my other tank. So, imagine my surprise when I found the attached on the underside of a piece of live rock tonight. This mass looks like a handful of spaghetti (same thickness and about 4" in diameter). It appears to be some type of egg mass, but the only thing that could have deposited it is the Sea Hare. Am I right on this? <Absolutely. These are sea hare eggs. Thanks for sharing. Do you know the National Resource for Aplysia at the University of Miami? You'll find information on the lifecycle, larval stages there. Rearing procedures are also briefly described on their website http://aplysia.miami.edu.> Thanks! Andy
<Welcome. Marco.>

Help ID Tank Spaghetti II  11/14/08 Wow, thanks Marco. Does this mean I'm going to have 8 million Sea Hares in my tank? <No, are they fertilized at all? I thought you only got a single specimen.> In the normal tank, would most get eaten by fish, corals, etc? <Even if you had two and the eggs were fertilized, few would have a chance. Not all would be eaten, the rest would be filtered, skimmed. If you want to raise sea hares you need at least two, and contact the National Resource for Aplysia and see their site for Aplysia production.> Thanks again. Andy. <Cheers, Marco.>

Help ID Tank Spaghetti III  11/14/08 I assume they are not fertilized--I have only one specimen, and I have had it for 4 weeks or so. I have no interest in raising Sea Hares. Thanks for your help. <Welcome. Marco.>

Nudi? Possible Sea Slug -- 5/3/08 Hi guys <Hi Ian, Lynn here this morning.> I think I saw a Nudibranch but not sure. It was highlighted on the front glass panel otherwise would never have noticed. It was a tiny yellowish worm looking slug which was about 10mm in length and 2mm wide. It was moving like a Nudi and had two little feelers on its head. <It does sound like a sea slug of some sort.> Please help me to ID this and if a Nudibranch could it be a pest? <Sorry, Ian, but without a good photo I can't even begin to narrow down the search. As far as it being a possible pest, it's undoubtedly a pest to something, but what I have no clue. A lot of these guys are obligate feeders, feeding on one specific food item and that's it. Once that food source disappears, so do they. Have you noticed any damage to your resident corals/cnidarians (if you have any)? If not, chances are good that this little slug isn't too much cause for concern. You may see it out an about for a bit and then no more.> I have not recently introduced anything into the tank but at this size it could have been around for a long time without being noticed. <Many are nocturnal but can be seen in systems during the day when they're running out of food. Also, some are cryptically colored/adorned so that they blend in unbelievably well with their surroundings - which in quite a few cases is what they eat!> Your help is appreciated. <You're very welcome, Ian. For more information and help in narrowing down the possibilities, please see the following links (as well as the highlighted links at the tops of the WWM pages): Sea Slugs: http://www.wetwebmedia.com/seaslugsopisthobranchs.htm Nudibranchs: http://www.wetwebmedia.com/nudibran.htm Sea Slug Forum: http://www.seaslugforum.net/ > Cheers Ian <Good luck! Take care, -Lynn>

Re: Nudi? Possible Sea Slug -- 5/3/08 Hi Lynn <Hi Ian> Thanks for your prompt response. Will check out the web pages you sent. <Sounds good. What you want to do is look for shared traits in the species of sea slugs/Nudibranchs shown at the WWM links I provided. That should help you narrow the search to family level. After that, go to the Sea Slug Forum and compare each individual species listed under that family. It can be tedious and time consuming, but ultimately rewarding! Here's a quick link to the SSF species list: http://www.seaslugforum.net/specieslist.cfm > Cheers for now Ian <Take care and let me know if you're able to ID that little fellow! --Lynn)>

Please ID: Sea Slug - 4/19/08 <Hi Cynthia> I am new to Nano-reefs. I actually went into the LFS to buy a small freshwater tank and ended up walking out with a 14g Bio-Cube. <Nice!> Please ID this weird white slug/worm that was hitchhiking on a turban snail. It's now on my live rock. I've exhausted myself searching the web and looking at photos of worms, snails, slugs. It does have 2 hornlike tentacles on its head. <Unfortunately, I can't see enough of the little guy to tell exactly what it is other than a sea slug of some sort. You might want to look through the various families/genera at WWM for shared/common traits including general shape, ornamentation on the back, shape of rhinophores (hornlike tentacles on the head), etc. Then go through the individual species listed under that family or genus at the Sea Slug Forum (link listed below). Also, keep in mind that these creatures do vary in color and can even fade and turn white if they're starving. Identifying sea slugs can be a big challenge, but you should be able to narrow it down to family given the links below. Also, be sure to go over part 3 of Bob's Nudibranch article for more general information regarding keeping, etc. http://www.wetwebmedia.com/nudibran.htm http://www.wetwebmedia.com/seaslugsopisthobranchs.htm http://www.seaslugforum.net/ Species list at SSF: http://www.seaslugforum.net/specieslist.cfm > Thanks Cynthia Rice <You're most welcome and good luck on your search! -Lynn>

Infected Tank??? Aplysiid sel.   4/1/08 Hi Bob, <Cynne> Hope this finds you well. Once again I have encountered a question regarding stock. The tank is the same as I described before. I now have 90 % of the Scorpions on frozen food, as well; I have followed your advice and purchased the Aqua C Remora Protein Skimmer with Mag 3 pump. I also have increased to a 4-6 inch sandbed with some aragonite. The Scorpions are so much fun :) I cannot believe that I enjoy them even more than the seahorses. <Both have/exhibit interesting behavior for sure> I no longer have the starfish; I sacrificed him about 2 months ago for a CopperSafe ich treatment (entire tank). I had to choose between the $17.00 starfish or the $1000.00 fish. I have since changed all filter media, changed 100% of the water in 25% intervals over a couple of weeks and rebuilt the biological with rock rubble from the LFS. I also continue to run poly filters and charcoal in the Aqua Clear. My question is I recently purchased a sea hare. I have always wanted one, but was afraid of inking. <Mmm, not an issue with many... tropical species. Unfortunately there is a current rush of selling large, non-tropicals...> I have searched your site but am still unsure as to what I have. According to one of Anthony's replies, I found that any Sea Hare with tassels is Carnivorous? <Mmm, no... not a sure characteristic> The pet store said this one was a Herbivore and they weren't sure regarding toxins. I also found one currently running on EBay and according to the seller; this guy isn't toxic http://cgi.ebay.com/NANO-Hairy-Sea-Hare-Reef-Aquarium-Live-HAIR-ALGAE_ W0QQitemZ290207618335QQihZ019QQcategoryZ66788QQrdZ1QQssPageNameZWD1VQQ_ trksidZp1638.m118.l1247QQcmdZViewItem. They also advertise this as a Nano size, Yet he looks a lot like the one on your FAQS page 2nd photo. <Mmmm... is this Bursatella leachii? Am thinking so... get's a bit large for nanos, but is tropical...> I bought him in NC, I am desperately hoping he is not a cold water species. He is fat bodied brown to green in color with black splotches. He also has baby blue specks all over the body and head, as if someone splashed paint on him, and he is tasseled. Please help I can get whatever food he needs. I just need to know what to expect. The fish do not mess with him at all and all intakes on filters and power heads are covered. Thanks again for all your advice!! You guys are great!! Cynne <Do see the Net (Google images et al.) for pix, ID... BobF out in Borneo>

Re: Infected Tank??? Seahare ID   4/4/08 Hi Bob, Thanks to all of you once again for quick response and intelligence beyond compare. You pegged it!! Bursatella Leachii he is. I could not find him on your site, and the internet was still a little contradicting. So what to feed? Life expectancy? Toxicity? Thanks Again Enjoy Borneo!! Cynne <I know naught other than what can be found on the Net also... did collect/culture Aplysia californica years back... but this is about all of the group. BobF, done diving and headed back tomorrow>

Surprise critter: Sea Slug? ID sources - 1/5/08 Hi all, <Hi Richard!> First, thanks for sharing so much info on WWM - it's a big help! <Thank you, it's our pleasure!> I've just set up my first marine tank (after 20 years of FW tropical). <Such a wonderful, rewarding hobby -- welcome to reefkeeping!> It's been cycling for nearly 2 weeks. I kicked the cycling off with about 4kgs of LR, which I'm told came off the Victoria coast (Oz - I'm in Melbourne). <Lucky you! I am determined to get to Australia one of these days. The Great Barrier Reef has always been at the top of my list of places to see/explore.> Ammonia and nitrates are currently at 0ppm, although nitrites are at 2.5. <Will subside/cycle out.> I've got a healthy supply of copepods & amphipods flourishing already, also some snails. <Yay!> Tonight I happened to pass the tank with the lights off and spotted something strange on the back glass. I turned on the lights and saw what appears to be a small sea-slug. Unfortunately due to the amount of algae starting to grow already, my camera wouldn't focus, so no photo I'm afraid. <Darn.> It's a teardrop shape, about 15mm long, 5 mm wide and a brownish red in colour. It has two white feathery antennae at the thin end of the teardrop and three small white spots on it's back - almost a small smiley. <Oh I know, I know! It's the rare and elusive Smiley Nudibranch, family Smileyidae -- just kidding <g>. Sorry, I couldn't resist!> It's quite flat, although the centre of the back is raised about 3 mm. Any suggestions as to what it could be? <Unfortunately, there are just too many possibilities and without a photo...?> I'm planning on keeping seahorses in the tank in another month or so <Go slowly here.> and I'm trying to avoid nasty surprises. Algae eaters would be fine though... <Understandable. If it were me, next time I saw that little guy, I'd get him out of there.> Also, is there any kind of marine creature search engine on the web into which you can enter distinguishing features? <Not per se - that covers all marine creatures. At least, not that I know of.> Seems like something that would come in very handy for many people :-) <Yes, indeed! In lieu of one specific search engine, there are many sites on the web that can help (including WWM!). I'll give you some of my favorites. The first will be of particular use for you as it covers crustaceans of southern Australia. You may find some of the amphipods/copepods/etc. populating your tank here: http://museumvictoria.com.au/crust/page1.html Here's another site that's run by a friend in the Philippines: http://home2.pacific.net.ph/%7Esweetyummy42/hitchhikers.html This site is Dr. Shimek's dichotomous key -- very handy indeed! http://www.ronshimek.com/Invertebrate%20Key%20to%20Major%20Taxa.htm Great sites regarding Sea Slugs: http://pick4.pick.uga.edu/mp/20q?guide=Rhabditophora&flags=not_no http://www.wetwebmedia.com/seaslugsopisthobranchs.htm http://www.seaslugforum.net/ I hope these help. I've got a gazillion more on file, but these should get you started!> Many thanks, Richard <You're very welcome! Take care -Lynn>

Update: New marine tank with surprise critter - Nudibranch? Sea Hare - 3/8/08 Hi Lynn, <Hey Richard! How's my favorite Aussie doing?> Thanks very much for the info you sent me. <You're very welcome.> The 'smiley slug' disappeared for a little while, but a couple of weeks ago surfaced again. <Neat> It's grown somewhat (35mm+) since I last saw it, and I just wanted to let you know that I'm now sure it's Dolabrifera dolabrifera, the algae eating sea hare. <Yay, congratulations and good on you for figuring out what it is! Thanks, also, for letting me know. Neat little creatures like this tend to lurk in the back of my mind until they're identified.> In fact, I seem to have about five of them, and although the smiley looked quite different when it was young (appeared to have a smooth back and white markings), the similarities between the mature hares really make it obvious. <Awesome> Now that I've watched them in action for a few weeks, the following are pretty clear: - They don't eat anything other than algae. - The colours come from the particular algae that they're eating (slowly changes over a period of 5 - 6 days). Seems likely that the red pigment doesn't penetrate all parts of the body - he's now pinkish brown with green ears :-) <Heeeee! It's the Easter Sea Hare!> - They're indifferent to what colour slug they mate with. - They're not the smartest critter in the world and often can't tell the difference between a rock and a seahorse (much to the surprise of both parties when they go for a ride) <Wheeeeee! Yep, it doesn't exactly sound like they're sharpest tacks in the drawer!> Cheers, Richard <Thanks again, Richard, for following up with this and for sharing your observations! Take care and have a great weekend, -Lynn>

Sea Slug ID: Elysia crispata? Need more information -- 2/3/08 <Hi there, Victor!> About one month ago, I acquired some live rocks from the southern part of Puerto Rico, after curing them I placed them in my marine aquarium. Last week I noticed an odd creature, which I assume to be some type of sea slug. It is completely white in color with two antennas and its back is completely covered with white corkscrew strands. Two days ago I discovered two more of these creatures, one measures 1 1/4" and the other two 1". To my surprise, the larger one merged with one of the smaller species and today I noticed pasted to the glass what looks like a corkscrew rope in a circle, I assume these are eggs. <You assume correctly!> At first I thought that these were Lettuce Sea Slugs (Nudibranch) but this species is not completely white nor do they have those corkscrew strands on their backs. My question is: What species are these creatures and do they represent a threat to my marine community? Almost forgot, I have never seem them on the bottom, they are always on the glass and move slowly just like a snail. <Hmmmm, here's one possibility, Elysia crispata. If that's it, I'm going to go buy a lottery ticket! Please see these links: http://www.seaslugforum.net/factsheet.cfm?base=elyscris and http://www.seaslugforum.net/display.cfm?id=10414 If that's not it (or if it's close), then an ID is going to take some research. What I would recommend is to go through the following links and try to determine which family your sea slug shares the most characteristics with. Start here: http://www.wetwebmedia.com/seaslugsopisthobranchs.htm . Then see the three pages starting here: http://www.wetwebmedia.com/nudibran.htm , especially the section on page 3 titled 'The Big Three Aquarium Problems with Nudibranchs'. Once you determine a likely family, you can then go to the Sea Slug Forum and look through the species listed in that family: http://www.seaslugforum.net/. It's a lengthy process, but you might just find your little slugs!> Best Regards and Thanking you in advance, Victor. <You're very welcome and good luck! Take care. -Lynn>

Sea Slug Id -- need more info -- 10/11/07 Hi, <Hi there!> I have a reef aquarium and recently found a sea slug in it and I am having trouble identifying it.
<Understandable, can be a challenge.>
The closest thing I can find that it resembles is the Janolus cristatus but I live in Florida in the United States so I am not so sure that it could possibly be that. <So it was collected locally, then?) The next closest thing it resembles is the color of Berghia but not Berghia. It has a wider body with much longer cerata. I assume it is nocturnal because I have only seen it out at night. <Okay> It also moves much faster than Berghia. I have Berghia in a separate aquarium. If you have any ideas about what it could be or could point me in the right direction I certainly would appreciate it much. <Well, a photo would be great here, but I can refer you to an excellent site for research: http://www.seaslugforum.net/. While there, do go through the species list (http://www.seaslugforum.net/specieslist.cfm) and check the links for genus Phyllodesmium, under the Family Glaucidae - as well as these species for comparison: http://www.seaslugforum.net/factsheet.cfm?base=dondocci http://www.seaslugforum.net/factsheet.cfm?base=phidlync http://www.seaslugforum.net/factsheet.cfm?base=learpoic http://www.seaslugforum.net/factsheet.cfm?base=learevel > Thanks in advance, Tariea Haywood <You're welcome, and good luck! --Lynn>

Sea Hare ID  -- 09/25/07 Hi Bob, <George> We took a shot of this animal and although it seemed like an Aplysia dactylomela at first we have second thoughts now. First because it was shot three days ago in the Mediterranean (and not the Caribbean) and second because it doesn't show the typical "wings" on its back. <Mmm, yes, but...> Do you know what this species is ? Needless to say, you can use the photo for your site (a higher definition photo can be sent to you if you need it for publication). <Looks like Aplysia dactylomela to me...> Best regards and many thanks,
George Reclos

Re: Weird White Pod or Sack on Tank - Looks Like Something That Was Attached to Alien Or Syconoid Sponges Identity Crisis - Dying Gracilaria  -- 5/19/07 <Hello Earthling, now called Dan, Mich with you again.> Hmmm, I think the problem is one in the same Mich.  More in depth look in the fuge.  This pod seems to turn into a two antennae white slug. <Mmm, nope!  You have two different creatures here.  Sea Slugs and Syconoid sponges> I've seen two crawling in the fuge...very small & they appeared white. <These Sea Slugs look to be of the order Sacoglossa or Sap-Sucking slugs which feed mainly on algae.  Likely they are part of the genus Elysia.  More here: http://www.wetwebmedia.com/seaslugsopisthobranchs.htm > This one in the pic was in the tank... not so white. <Perhaps greenish?> Also is a pic of what I would call a bunch of Pupa entwined in the Gracilaria. <Nope, still Syconoid sponges.> Thanks with the help. <Welcome!> Man I am scratch'n for an answer...   <I won't ask where...> with out the Gracilaria, my nitrates are beginning to rise. <Gracilaria can be a challenge to grow.  If it's growing sponges, it's not tumbling enough.> I could put Chaeto in there but would that be fuel for these things as well? <No, but Chaeto or Caulerpa may be a better food source for the slugs which can be difficult to keep in captivity.  Mich> DanH Picture Too Large!  5/18/07 <Please return with a smaller picture attached.  This one is overloading out bandwidth.  Thanks, WWM Crew> <No worries.>

Help ID this slug   5/10/07 Some people on Reef Central think it's a slug but not sure what type or if it is reef safe. Could it be a Sea Hare? I found it at night underneath my Molokai LR. Does it eat algae? Thanks. <Is a Common Sea Hare (or Kualakai in Hawaiian), Dolabrifera dolabrifera (Rang, 1828), Family Aplysiidae... Do feed on algae, live under rocks intertidally! Nice pix! Bob Fenner>

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