Staurosirella moralesii Van de Vijver, Jüttner & D.M.Williams sp. nov., SEM micrographs taken from the type material (ANSP G.C 100049b, Willow Creek, United States). A–C. SEM external view of three complete valves, showing the variation in the shape and size of the sternum, the differences in shape and size in apical pore field between head- and footpole. D. SEM internal view of a complete valve. E–F. SEM view of the valvocopula with the fimbriate extensions in oblique and frontal view. Scale bar = 10 µm.