Klas Malmberg Aquatilis Very much thank you, Christian Skauge and Erling Svensen, for the information of how to find Cumanotus beaumonti! Now it is proved that this nudie also lives i Sweden...
Erling Svensen Good work and congratulations.
Christian Skauge Congrats Klas, great find!!
Erling; let's bill him :-)
Terry Griffiths Stunning for Keith Hiscock Eastern Kings today
Terry GriffithsCumanotus beaumonti if i am correct.
Sarah Bowen Ooh, love it! Top of my wish-list - have seen its food-source a few times but never the nudibranch. Is this just one animal or animal plus hydroid, or what?!
Terry Griffiths @ Sarah this was two mating at the base of the hydroid also another one about 12 inches away also have photo of their eggs.
Kate Lock Gorgeous! makes me go all pink and fluffy!
Klas Malmberg Aquatilis How to find Cumanotus beaumonti. Search after the hydroid Corymorpha nutans and there they are... pictures from Sweden today.
Erling Svensen Yes, Klas. Just find a big colony of C. nutans and start searching. I wonder how the C. beaumonti find the colony. That is more interesting to know.
David Kipling Many nudibranch species have planktonic larvae that settle and metamorphose if they touch their food source as they drift by. I'm not sure if that applies to this species (some nudis have direct development, with no veliger).
George Brown What laid this 50mm long spiral of eggs on shell sand?
Chris Barrett Where was it found? Some elasmobranchs lay eggs like these
George Brown Hi Chris Barrett. Found on a gentle slope of shell sand, Les Dents, Sark. If you zoom in hundreds of tiny eggs can be seen, each the size of a pin head. They look suspiciously like mollusc eggs. Please excuse my ignorance but I thought elasmobranchs laid "mermaid's purse" like eggs? The egg mass in the photo is extremely delicate.
Chris Barrett I think it depends on the species. Elasmobranchs like dogfish and also skates and rays lay the mermaids purses, but i think species like Horn sharks lay the spiralled eggs. Not familiar with species of Sark though, so don't know if you get many sharks there. Like you say though, could just be mollusc eggs, especially given the size! :)
Chris Barrett I was thinking of things like this, although they're much bigger: http://www.google.co.uk/imgres?q=shark+egg+spiral&um=1&hl=en&safe=off&sa=N&biw=1366&bih=643&tbm=isch&tbnid=lkgy8a-iXc5X1M:&imgrefurl=http://www.nmfs.noaa.gov/rss/podcasts/weirdfins/sharkspurse.htm&docid=H44r1pXKl9o3SM&imgurl=http://www.nmfs.noaa.gov/rss/podcasts/weirdfins/images/Horn_shark_egg_case.jpg&w=432&h=432&ei=n4CyT6j7G4i18QPe8fGbCQ&zoom=1&iact=hc&vpx=202&vpy=136&dur=1132&hovh=225&hovw=225&tx=131&ty=91&sig=104821394047395528907&page=1&tbnh=139&tbnw=189&start=0&ndsp=18&ved=1t:429,r:0,s:0,i:72
David Kipling I've seen those spirals as well and had assumed some mollusc (based on no evidence other than looking like nudibranch eggs!).
David KiplingPleurobranchus membranaceus lays eggs in spirals somewhat like this (see post by Jim Anderson).
http://www.seaslugforum.net/showall/pleumemb
George Brown Hi Chris. Excellent image but I think you could drill for oil with that! The spiral is much more like what David suggests. Jim's beautiful images of Pleurobranchus eggs look more "bloated" but his correspondence with The Sea Slug Forum suggests they "take on water". Maybe they've just been laid? Having said that and the eggs exhibiting the same "left-hand" thread, I'm familiar with Pleurobranchus (and their eggs) but didn't see any in the immediate neighbourhood.
Jim Anderson This doesn't look like P. membranaceus to me from the size of the sand grains stuck to it ad the general shape.
Jim Anderson Maybe Cumanotus beaumonti (Eliot, 1906)
Jennifer JonesOkenia aspersa spawn?
David Kipling Thank you Jim, I was racking my brain trying to remember! I knew it was something exciting; I'd been advised to look for that nudi if I saw such spirals.
David Kipling Although looks a little different to the egg picture on SSF for C beaumonti:
http://www.seaslugforum.net/showall/cumabeau
David Kipling The SMNR nudi survey has (as Jennifer suggests) pic of Okenia aspersa spawn that look like this, and they found a lot. See p21 of the 2010 report here:
http://www.ccw.gov.uk/idoc.ashx?docid=da531252-994c-4a68-ad51-d23f209505a9&version=-1&lang=en
Kate Lock Yes I definately agree with Jen Jones - Okenia aspersa....we photographed both the nudibranch and loads of the eggs during the 2010 survey - very distictive corkscrew eggs usually found in sediment areas where Mongula oculata is found (O.aspera food)...
Kate Lock Glad to see our nudi survey report has been useful!!
Erling Svensen Are you sure about the Okenia? lokk here. http://uwphoto.no/shopexd.asp?id=1192
Keith Hiscock Yup, Pleurobranchus membranaceus eggs - 2008 was a 'good year' for them in Plymouth Sound - watched the slugs lay them and quickly scoot off at a rate of knots across the mud. Images available.
Kate Lock I shall check when in the Skomer office tomorrow - Bernard Picton was on the dive with us and took several pictures of the O.aspersa eggs - I have these on the files so can check them....think we could have some Pleurobranchus ones to compare too...
Erling Svensen I am quite sure it is Pleirobranchus
George Brown Looking at the evidence I'm with Jennifer Jones. All the Pleurobranchus eggs I've seen are much bigger and not as tightly coiled as the ones in my photo.
David Kipling I've seen these eggs also in Sark (which is where George took this pic) and my recollection is that they are smaller, thinner and a different spiral shape to the Pleurobranchus eggs that I've seen (and I know that's what they were because the adults were alongside). Actually, having said that I may well have some pics of the latter to help ... job for tomorrow!
Claire Goodwin Pleurobranchus eggs are much bigger and I think maybe a flat spiral rather than a coil (need to check pics!). I'm with Jen, Kate, George et al. in that these are Okenia aspera. We also have a similar spiral in the museum database from Okenia pulchella - though this is listed as a probable variety of O. aspera on Habitas (O.elegans are very different, orangeish and more tangled ribbon like).
Keith Hiscock I should have been more careful about scale and I am now (easily) persuaded that the eggs are not of Pleurobrancus as too small.
David Kipling Could someone post some Pleurobranchus egg pics in the folder so we have a comparison for future reference?
Kate Lock I have just put in the 'egg identification' folder a picture of each taken on the Skomer nudibranch survey 2010....we saw the beasties too so have proof of who laid the eggs! Hope this helps for future reference.
Peter H van Bragt Not likely, but I must also say that I have no idea what else it might or could be. Pigmentation looks like Cumanotus beaumonti, but it doesn't seem to have cerata in front of the rhinophores. How small was this slug?
Arne Kuilman Doesn't look like the juveniles I've seen and Peter's seen even more. Would be new to me if I saw this in Dutch water.
Klas Malmberg Aquatilis Slug was 11 mm, Cumanotus has very long and small cerata so I do not think thats right, the pigmentation at the face is why I do think its a Aeolidia but I still think its a strange form. I think it looks like combination of Aeolidia papillosa and Eubranchus pallidus... so any other suggestions?
Rudolf Svensen Anybody knows this one? Image captured South in Norway on a dive today. I guess it was maybe 10 mm long.
Terry GriffithsCumanotus beaumonti i think would be a good starting point.
Floor Driessen Could this be Cuthona nana? (It feeds on Hydractinia echinata)
http://www.habitas.org.uk/marinelife/species.asp?item=W14710
Rudolf Svensen I do not the mout/head looks like Cumanotus beaumonti so I guess it is closer to Cuthona nana.
Peter H van Bragt Considering size and number of cerata C. nana comes very close. C. beaumonti has cerata in front of the rinophores and there seems to be too many cerata for a juvenile C. concinna or C. gymnota.
Christian SkaugeCuthona nana would be my guess too :-)
Christian Skauge Still plenty of nudibranchs at the house reef of Gulen Dive Resort, Norway: Cadlina laevis, Cuthona rubescens, Cuthona gymnota, Flabellina nobilis and the illusive Cumanotus beaumonti - to mention a few :-)
Klas Malmberg Aquatilis Fina bilder! Jag lÃĪngtar dit!!!!!
Arne Kuilman Stunning stuff there. What's the best time to dive there for nudibranchs?
Christian Skauge Just wanted to test uploading a video :-) This one shows a Cumanotus beaumonti sitting just below the tentacles of a Corymorpha nutans hydroid - its preferred food.
Christian Skauge Okay, something happens... the image is a little compressed sideways.
George Brown Looks perfect on my screen. Well done Christian!