Staurosirella jonssoniana Van de Vijver & Iris Hansen, sp. nov., LM and SEM micrographs taken from the holotype material (BR-4843, Grenlækur, southern Iceland) A–U LM pictures of valves in valve face view in decreasing length V–X SEM external view of three complete valves with focus on the spines located in pit-like depressions. Note the absence of apical porefields Y SEM internal view of a complete valve. Scale bars: 10 µm (A–W, Y); 1 µm (X).