More specifically - Navicula saprophila Lange-Bertalot & Bonik

 Mojord,

The bottom five of this might be it:

http://ccmp.bigelow.org/SD/mapsearch11.php?klass=&genus=&species=&mapfile=Log-bathy.90.N.180.W.100.png&buffa=All&classnames=0&commonnames=CommonNames&commondef=&strain=&szmin=&szmax=&tempmin=&tempmax=&axenic=&general=navicula+saprophila&toxic=

Or try this:

http://ccmp.bigelow.org/ 

I see SERI has it.

It seems that U of Hawaii also does.

Thanks, I'll check them out!!