Chrysophycean siliceous stomatocysts are primarily known from freshwater environments, and limited research documents their presence in marine settings. Some hypotheses suggest that these cysts may be transported from freshwater sources into marine environments through rivers or wind, explaining their occurrence at sites like the Porcupine Abyssal Plain. It is uncertain if they are transient freshwater cysts or adapted marine populations. Molecular analysis or stable isotope studies could help clarify their origin. Documenting your observations with SEM images could contribute valuable insights to the study of chrysophyte distribution in marine environments.

Hello, thank you for your answer. I have SEM images showing basically the same morphotypes as those documented in fresh water (https://plankton.mio.osupytheas.fr/apero-chrysophytes/). They are in really good shape and prevalent in my samples (they are in half my samples), so I was wondering if they could survive a while in the marine environment as cysts do in adverse conditions. There are 2 papers apparently describing them in the Indian and Southern Ocean, but they are in Nova Hedwigia and I don't have access to this journal. :-( Molecular analyses are coming as well. Best.