marine-brackish diatom

[Rene]

Hello,

Who can give me a name for this Melosira?? Usually I only come across M. moniliformis and M. nummuloides, but this one is different. Also, the usual ID guides don't mention anything about the choroplasts.
From the Dutch delta area (Oosterschelde), preserved with Lugols iodine. Objective 40x/0.95.

Thanks, René