It was originally posted as image #3 at https://www.photomacrography.net/forum/viewtopic.php?t=45507 .
We're reproducing the image here, separately, as part of our procedure to provide clarity when the front page shows one image from a larger collection.
Please discuss in its original thread, with cross-references as needed. Thanks!
--Rik
Diatoms: Epithemia sp. dividing (Beatsy)