Staurosirella stoksiana Van de Vijver, sp. nov., LM and SEM micrographs taken from the holotype material (BR-4842, Voorste Nete, Dessel, Belgium) A, B LM pictures of a frustule in girdle view C–AD LM pictures of valves in valve face view in decreasing length AE SEM external view of a complete frustule in girdle view showing the girdle structure and the mantle AF Complete view of the valvocopula with the large fimbriae AG SEM external view of a complete valve with focus on the apical pore field and the depressed headpole AH SEM internal view of a complete valve AI SEM external view of a complete valve in girdle view AJ–AK Two SEM externals view of a complete, heteropolar valve. Scale bars: 10 µm.