Unknown object from the Baltic Sea - Radiosperma corbiferum

[Klaus Yde]

Can someone help me identyfiying this:

It is about 200 my across. It appeared  behind a squashed Polychaete species (polydora). The sample was a fresh planctonsample just taken in Green belt in the Western Baltic sea. I am not sure if it is a part of the polychaete or separate from it - My guess it is some Fish Egg but would like to get some help.

The picture is taken with DIC on a Zeiss Jenaval using a 25x planapochromate. The picture is stacked and has got a little brushup in Photoshop.

Just answer in German

Kind Regards

Klaus Yde

[bini]

Hi Klaus,

first, my English is not good, but I try... 

I think the following link shows on page 231 - Plate 5.3.35 - the same object you found in your planctonsample:

http://www.io-warnemuende.de/tl_files/forschung/meereswissenschaftliche-berichte/mebe76_2009-zooplankton-extended-atlas.pdf

There is written: "Protista, unidentified species of Heliozoa, diameter with axopodia ca. 80 μm"

Friendly Regards
Bini

[Klaus Yde]

Hallo Bini

I think You are right - and thanks for giving me the reference also, I have just ordered it for my library.

I have thought a lot of the object - and one of my ideas is that it could be a internal parasite of the squashed Polychaete - I have been looking in it - but not found anything so far. I have some of the living sample in my refrigerator and will try to find another specimen later

Thanks

Klaus Yde

[bini]

Hallo Klaus,

You´re welcome!
Try, maybe you´re lucky. 

Kind regards
Bini

[Eckhard]

Hello Klaus,

beautiful find and picture!


@Bini,

congratulations on your sharp eye!

Regards
Eckhard

[bini]

Thanks Ecki! 

[Michael Plewka]

hi Klaus,
to me the object seems to be the adhesive disc of a Trichodina species.  Trichodina has been shown recently in this forum by Steffen Clauss. Trichodina lives as a parasite on freshwater  invertebrates like Hydra or copepods. Other species of this genus live as ectoparasites on the scales or gills of fish.
At least several dozens of species of Trichodina live in marine habitats as well. Maybe there are even specific  parasites living on polychaetes. The adhesive disc seems to be mad of material like chitin, so when the ciliate desintegrates the adhesive disc will still remain for some time.

best regards Michael Plewka

[Klaus Yde]

Hallo Michael

You could absolutely be right - but I am no specialist. I have read the thread by Steffen Clauss and seen his pictures. Mouth parts has also been in my list of posibilities and still are. I have Googled Trichodina and I se two problems: One: they seeem all to bee with very little variation and I didnt find any like my picture. Two: the seem all to be very small compared to my specimen.

I have yesterday posted the picture to the Marine Biological Section, Department of Biology, University of Copenhagen.

They were not sure about what is was but sugested that Heliozoa as Bini suggested absolutely was a posibility. They would send my picture around in the hope that some of their specialist could identify it.

If I get a identification - I will of cause post it here.

I still have the feeling that I have seen a drawing/photo of a similar specimen - and I will check my books again this evening

Thanks for the input.

Kind regards

Klaus Yde

[Rene]

Hi Klaus, I have absolutely no idea what it could be, but it doesn't look heliozoan to me.  The 'spines' sticking are no heliozoan axopodia, but who knows, the radiolareans are nearby. In any case, the spiralling near the cell body does look ciliatish, I agree with Michael about that.

Good luck, Rene

[Franz]

Es könnte sich um Radiosperma corbiferum (synonym: "Sternhaarstatoblast" Hensen) handeln.

Viele Grüße
Franz

[Michael Plewka]

hallo zusammen,
Gratulation Franz! Volltreffer!!!
http://images.marinespecies.org/16674_meunier-1910-plaat-6.jpg

beste Grüße Michael Plewka

[Rene]

wow, for a green algae, that is pretty bizarre.

Thanks Franz!

[Ernst Hippe]

Hallo,
ist das denn eine Grünalge? Nach veschiedenen Artikeln im Netz könnte es auch die Cyste eines Dinoflagellaten sein.

[Klaus Yde]

Thanks all for the help - Especially Franz. I am at the moment collecting information about the specimen. As I read it - there is not complete agreement about which kingdom it belongs to. If any find some more recent references - I would be very happy to get a mail with it.

Many kind regards

Klaus