Scanning electron microscopy (SEM) images of Ambo dajingensis sp. nov. in an external view of the entire valve A, B external valve view of the whole specimen. There is a hyaline valve face over most of the length and transapical striae develop only at the valve apex, with a weakly expressed sternum at the apices C, E, F fan-shaped spines (arrows) are arranged along the valve margin, there is striation, a strongly expressed sternum on the valve apical part, a small circular striated area structure on the mantle apex D the girdle bands. Scale bar: 1 µm.