obscure North Sea diatom

[René]

Hi guys, please have a look at the following slides, and tell me what it is??

Best wishes, René

[Gyrosigma]

??? new genus ???
never see before in my books
If I understood you seen it in 2008, 2009 and 2015 ??

regards

Dominique

[BJ]

Hello René,

a nice set of images and great dedication over a number of years.

My impression is that they might be zygotes or auxospores of a pennate diatom.
This could explain:
1. Why they do not look like any diatom you are familiar with
2. why the shape is very inflated
3. why the 'ornamentation' (striae etc) is weakly developed

However i have another possible explanation which in a sense is the exact opposite....

Could they possibly be the very small diatom cells (for that species) formed after repeated cell divisions at the end of a division cycle. In my experience they often have very dense cell contents and do not show the typical shape or features of the species.

....but then i like Dominique's idea as well.... a new genus...

Reneana

thank you for posting and please let us know if you resolve this,
regards,
Brian

[René]

Ha no, nothing strange with this one. In fact it is not very uncommon either and I see them every year.
It falls within the Plagiotropis group, but I'm not yet sure which genus.

Best wishes, René

[Jacek]

Interesting