Hello Olivier,
Thank you very much for your confirmation of the name of Micrasterias and for your compliment.
Mitch640,
This Micrasterias I found last year in the very small lake in the middle of the forest in Wigry National Park next to my home in Suwalki region in Poland. Water of this kind of the lakes is almost brown and you can find there a lot of desmids.
Regards
Marek