Mittwochrätsel

[Rene]

Time now for the Wodenstag Rätsel ;-)

I admit it is not really a happy cell...


Focussing at the surface gives more clues for identification:


So who's in for a guess?? As always, replies in any language are wellcome.

Best wishes,

René

[Heiko]

Hallo René,

ohne Deine Erkäuterungen hätte ich allerdings ein Pollenkorn "gesehen".

Grüße, Heiko

[TPL]

Hoi René,
muss wohl irgendein Dinoflagellat sein...
m.v.g. Thomas

[Rene]

Very good Thomas!

It is stained with a fluorescent brightener, one that makes your wash whiter then white (or so the slogan goes)  
This way the Panzer stands out, otherwise I probably wouldn't have spotted it in the sample:



Sample from das Wattenmeer, stack of 11 images with 20x/0.7. Width of the cell is 20 um
Identification to species is tricky, but the shape of the pore on top is a give-away for Scrippsiella.

Here's one, top view from another sample:



With this pore it can attach itself to a substrate, as the start of encystment (although I'm not sure all Scrippsiellas are able to do that).

Best wishes, René

[Klaus Herrmann]

Hallo René,

die ersten Bilder sahen etwas aus wie smashed potatoes   daraus Dinoflagellat abzulesen grenzt schon an Hellseherei -aber vielleicht ist es auch gutes Erinnerungsvermögen? Ich meine du hast die Bilder schon mal gezeigt?

Aber die Fluoreszenzaufnahmen sind phantastisch. 

Kannst du noch verraten:

fluorescent brightener

was ist das für einer und wie hast du angeregt (HBO oder LED?) und mit welchem Filterblock?

[Rene]

Hallo Klaus,

Mashed potatoes , old with a tough skin! Good comparison!

Anyway, the theca can just about be seen in brightfield, and with the apical pore and the girdle visible it is obviously a dinoflagellate. But I wouldn't have spotted it while scanning through the sample, if it wasn't for the fluorescence.
The stain is acually called Calcofluor White, commonly used as an additive in the paper industry and in laundry detergents. It binds specifically to cellulose and does also work with violet/blue excitation, for example with a fluorescein filter cube (ie with green emission). But I like the UV (DAPI) filter cube, as it gives 'true color' and I can mix in transmitted light while scanning my samples. I have Nichia UV-LEDs installed on our microscopes.

Best wishes, René