Aplidium punctum

David Kipling Firth of Lorn (Scotland), in relatively shallow water on red weed at the end of a dive. A little stalked squirt, it looked initially like a small Aplidium punctum but the red spot is not one spot but two, and they are on the other side of the zooid (and also the wrong colour). Anyone seen something like this before?

George Brown For David Kipling and Dawn Watson. A crop of an image posted earlier of Aplidium punctum. I'd suggest the orange spheres are eggs. Are the white, less spherical objects closer to the rock face eggs in an earlier stage of development?

Becky Hitchin Would make sense

Floris Bennema And lightbrown excrements at the opposit side I would guess?

David Kipling Yes, you can see the mucus rope being wound into a spiral as it goes down the gut and then back up again to wherever the anus is on these things.

David Kipling There is a nice series of diagrams of zooids in this reference: look at 17c for Aplidium. http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1676-06032012000100022

David Kipling The short answer is that going right to left you first have the stomach with vertical folds (ie L<>R in this picture). Then the U-shaped gut (with the lightbrown excrement that Floris Bennema notes) . Then you have the ovaries with developing orange eggs. Then you have white blobs which are the follicles of the testes; the sperm is collected into a duct that then runs all the way back up to release into the atrial cavity next to where the eggs are. And if you look even closer you can see what I think is food on the mucus net being wound into a rope at the dorsal lamina and then drawn into the stomach.

Floris Bennema Perfect information David Kipling !

David Kipling Annotated version of George's picture of Aplidium punctum. Would be interested to know how much of this I've got right!

George Brown Aplidium punctum, about 20mm long. Ardnoe Point, Sound of Jura. Water depth 20m.

George Brown Good question Dawn. I posted it because of the angle. It's what happens when you dive the Sound of Jura at "slack water" only to find the calcs are 3 hours out! Not my calcs, obviously. :o) Should I post a traditional angle, just to be sure? Don't want to be barking up the wrong squirt.

David Kipling I think it's a combination of strong side lighting and the black background that's making it more transparent and blue than usual flash-on shots on the reef. That being said, squirts do drift in their morphology [genetics, response to local conditions] so I wouldn't be in the slightest bit surprised if the Jura punctum looked a bit different to those in Norfolk. Bernard talks about having to "calibrate" his eyes in different areas for squirts (and sponges) for this reason.

Becky Hitchin Cor

David Kipling This is why you need external strobes Becky ;)

Becky Hitchin I know I know! I'm currently wondering if they are significantly cheaper in America, as a lot of things seem to be, as I'll be there in a few days time. And whether they have the same strobe systems.

George Brown Aplidium punctum, about 20mm long. Ardnoe Point, Sound of Jura. Water depth 20m. View looking into tidal stream.

George Brown Phew! You ask good questions. :o)

David Kipling Next question then (having had your starter for the George) - what's the red dot inside the zooid, near the base of the branchial basket (seen in the other picture)?

Erling Svensen Do anybody knows this one. I hope its a tunicata? Never seen anything like it. They are less then 1 cm long. Very exposed location in South West Norway yesterday. 15 meter of seawater.

David Kipling Is this more of the 'atypical' growth form of Aplidium punctum, like some pictures you posted a while ago?

Erling Svensen Yes, but that was 4 weeks ago (aprox.). Looks like eggs inside?

David Kipling Do you mean the L-shaped structure left and down of centre?

Erling Svensen Yes, and also to the right in the top.

David Kipling Oh yes, I see that. And a bit more bottom right.

David Kipling Looking at Berrill, I think that's the wrong place for eggs. They're show in each zooid, near the top and alongside the branchial sac. Each egg/embryo is about 1/5th the length of the BS. Those 'eggs' are thus too big and in the wrong place. I'm guessing they are immature zooids (budding or regression).

Erling Svensen Interesting. Thanks, David.

Erling Svensen Cropped number 2.

Erling Svensen I have some old pictures of one called Aplidium punctum, looks a litle bit, but not exactly the same.

David Kipling Ah, I can see what look like paired red dots on the zooids. (Eg the large blob, top edge of it, a couple of good examples there). So that's not A. punctum then, that'd be a single dot. The other thing that is curious (Sarah noted this) is the chimney-like projectiosn. The clump near the bottom shows this, it's almost like a common cloacal opening (which is wrong for an Aplidium, they are distinct zooids each with in and out siphons). Curious!

Anne Bay-Nouailhat Why don't you think of A. turbinatum? Colonies are similar, long thin stalks, small systems, with two red dots around the oral siphons. These ones have contracted zooids so the white markings are not shown but the common cloacal opening at the center of the colony can clearly be seen. Unusual aspect, but maybe water's too warm for them ;o)

David Kipling I hadn't realised that there was a common cloacal opening on Aplidium, but now I think of it I only see one opening per zooid so I guess the water has to come out somewhere! So are the zooids all opening into a single chamber with a common cloaca, Anne? Millar (Linnean synopsis) isn't that helpful on this.

Anne Bay-Nouailhat Yes, that's it.If there's a single system of zooïds, each of them opens into a single chamber and water comes out through a common cloaca.

David Kipling Yah! That's my "thing I've learned for today" (I like to have one every day). In which case I can see exactly why you think this is a contracted A. turbinatum, it all makes sense now. Thanks!

George Brown Is this Aplidium nordmanni with six lobes round each oral siphon? And is the tunicate to the right, with the orange spot on each zooid, Aplidium punctum? Many thanks.

Wilfried Bay-Nouailhat agree with you : A. nordmani and A. punctum

George Brown Thank you Wilfried.

George Brown I've been calling the red/pink tunicate in the middle of the picture Aplidium nordmanni. In view of what's been mentioned this last few days I'm now not so sure. Also what is the name of the pale tunicate at 12 o'clock and smaller specimens at 3 o'clock? Loch Eriboll and many other sites around the north.

Joanne Porter Is this the same thing we were seeing in Shetland George?

David Kipling Looks like nordmanni to me - 6-lobed siphons, single red lump with white bits.

George Brown Yes Joanne I'm sure it is. On all the exposed sites there were small examples of this dotted all over the place. And thanks for the confirmation David, it's the same formula I was using! Can you guys help me out with the paler, orangey ones? Many thanks.

Bernard Picton I've seen these George, but I don't have a name for them... Not even certain of that being A. nordmanni...

George Brown Many thanks Bernard. How very interesting. I've been seeing this from the Small Isles right up to Shetland so it's not rare. I can almost predict where it can be found. A. nordmanni till further notice?...

Richard Yorke The sooner we get a book the better, though these facebook pages are teaching me a great deal without one. I had been thinking that was Sidnyum elegans not Aplidium nordmanni but now you point out the 6 lobed siphons and I notice that Habitas mentions there is a pink form I realise I have got to go back and check and probably change the keywords on my pictures.

Richard Yorke As to your initial question George, the pale tunicates look very similar to the Aplidium punctum at 9 o,clock. Is there a form without the spot? I see from Habitas there is a form with white spots.

George Brown Many thanks for this Richard. Will check this out. Mind you, if Bernard is not sure, what chance does the rest of us have! I'm going for extreme close-up shots of inlet and outlets to assist future ID. Any other features we should be focussing on?

Bernard Picton Side-on to show colony shape at edge, stalk, etc.?

Mickey Luv

Mickey Luv very common in my local (Falmouth) rock pools recently but I am not sure what species this is... I am sure one of you does though!

Kirstie Harris Are you Mickey Luv after the League of Gentlemen character? :)

Mickey Luv I am afraid so....

Mickey Luv got it! Indeed a tunicate, Aplidium punctum. Tunicates are booming at the moment, both solitary ones and also Botryllus and Botrylloides.

Mickey Luv Probably a Morchellium argus actually, as they grow to about 4 centimeters

Rohan Holt If you look really close at the ends of the individual zooids you can see small red dots... four around each one. Makes this Morchellium :-)

Mickey Luv Thanks Rohan! Tunicates are tricky to identify I find. There are lots of Corella eumyota around as well but they are not featured in my (excellent) Collins guide. I will write a post about them on my blog this week (anbollenessor.wordpress.com)

Mickey Luv http://anbollenessor.wordpress.com/

David Kipling We had some discussions with Steve Bound and others about whether we are seeing Aplidium punctum or Morchelium argus on the Seasearch S Pembs weekend in May. I have therefore put together an album of what we saw last weekend - which was both in fact! - with some personal ID notes.

George Brown This is an excellent Seasearch contribution David. The way I differentiate these two is by: A spot v MORe spots.

David Kipling Oh I like that one George, very good! I shall remember that!

George Brown I have the memory of a headless chicken so have a suitcase full of these. Now where did I put that em, ....

David Kipling These are some pictures of a specimen of (what I hope is) Aplidium punctum, both in situ and dissected under the microscope to show the stomach folds. I've included the Millar Linnean synopsis pages for this species and Morchellium argus, which as I diver I also see and can get confused by.

David Kipling We had some discussions with Steve Bound and others about whether we are seeing Aplidium punctum or Morchelium argus on the Seasearch S Pembs weekend in May. I have therefore put together an album of what we saw last weekend - which was both in fact! - with some personal ID notes. I presume you get these in N Wales as well ;)

David Kipling Am I right in thinking that I should be referring to Sidnyum (eg elegans, turbinatum etc) more properly as Aplidium? http://www.marbef.org/data/aphia.php?p=taxdetails&id=103441

David Kipling Actually it's Aplidium on NBN: http://www.searchnbn.net/gridMap/gridMap.jsp?allDs=1&srchSpKey=NBNSYS0000177968

David Kipling Same is true for Aplidium elegans as well ...

David Kipling This probably explains why there are no records for these species in Norfolk ;)

David Kipling We have every intention - roll on Aug!

David Kipling Kate Lock and my carer are certainly coming. Does Becky Hitchin know about this as well?

David Kipling A week of squirts should temp Becky out of Kent ;)

Kate Lock Lalalalalalalalalalala I am with Dawn Watson on this one......

David Kipling So Kate and Dawn ... doesn't marine recorder beep an error at you when you try and enter Sidnyum (since it's out of date)?

Kate Lock I hate databases....and MR does not like Macs and I like Macs so I kindly pass on all the forms to that nice Jennifer Jones to do the MR entry and earn some extra winter holiday money!!

Jennifer Jones No David, it accepts Sidnyum but not Aplidium

David Kipling Aplidium nor Sidnyum on NBN and WoRMS... argh!!!

David Kipling But which is correct?

Paula Lightfoot According to WoRMS Aplidium is accepted and Sidnyum is unaccepted. MR will get there! http://www.marinespecies.org/msbias/aphia.php?p=taxdetails&id=103683

David Kipling Dawn's going to go all punk and rebellious on me and stick with Sidnyium now!

Becky Hitchin I'm sure I've managed to enter Aplidium into MR!

Paula Lightfoot Aplidium elegans is in the MR look-up table (since Nov 07) but Aplidium turbinatum is not, only Sidnyum turbinatum.

Becky Hitchin and Aplidium punctum is in there I think?

David Kipling And hopefully Aplidium glabrum, nordmanni and pallidum?

Paula Lightfoot yes yes yes and yes! but I don't think punctum ever was a Sidnyum, whereas elegans and turbinatum were...I think...I'm getting confused by all these squirts!

David Kipling For those of us who use Habitas, it's really only these two Sidnyum/Aplidium species that are different between Habitas and NBN. Phew!

Jennifer Jones I wasn't saying Aplidium spp weren't recognised in MR, I was talking specifically about the species mentioned!

David Kipling I know, we just got paranoid Jen ;) Having spent way too long today going through every ascidian entry on NBN I am now a little spooked by just how many Didemnum species have been recorded in the UK. Those are going to end up in a "flat sheet with holes" category at this rate (alongside "thin orange crust", a phrase that covers a multitude of sins...).

Jennifer Jones Now maybe you understand why I won't name a lot of sponge crusts without thorough investigation!

Becky Hitchin At least D. vex is included in MR now :)

David Kipling But no map data on NBN, correct?

David Kipling Comparative photos (same camera, same dive(s)) of A. punctum versus Morchelium Argus to try and document the different "feel" of each species in the field.

Anne Bay-Nouailhat all the more, M. argus has 4 red dots on top of the oral siphon wheras Aplidium punctum has only one.

David Kipling Yes indeed Anne! However this is difficult to see by the naked eye underwater, and many of our Seasearch divers will be doing surveys where they do species ID based purely on underwater observation, as opposed to taking a digital picture and checking for 1 v 4 spots. Hence the need for the overall "feel" as well.

Paul Freeman could someone tell me what these are? https://www.facebook.com/photo.php?fbid=10152966431775352&set=a.10152966414020352.1073741838.712350351&type=3&theater

Richie West they're sea squirts (ascidians) Paul, looks like Morchellium argus http://www.habitas.org.uk/marinelife/species.asp?item=ZD460

Michelle Hooper I'd go with a sea squirt colony 'Aplidium Punctum' or 'Morchellium Argus' if you mean the white 'fluffy' looking masses :).

Paul Freeman yup - thanks

Michelle Hooper Just out of interest what camera and housing do you use. I'll have to update mine one day! :)

Paul Freeman i had a fuji f30 'till last week - flooded :-( now have a fuji f80 exr. quite pleased so far (only done 2 dives - in the same day)