FIGURES 148–152. Ralfsiella smithii (=Cerataulus smithii Ralfs in Pritchard) (Beaufort, South Carolina, USA). Fig. 148. Circular valve face with opposing narrow submarginal elevations; positioned midway submarginal hollow spines, the exterior openings of rimoportulae; valve surface covered in a mostly radial pattern of false pseudoloculi, valve mantle slightly indented where it joins narrow hyaline valve margin; scale bar = 10 μm. Fig. 149. Summit of elevation with rimmed ocellus; scale bar = 2 μm. Fig. 150. Frustule with attached girdle bands, flat valve face merging into rounded mantle, barely raised elevations; scale bar = 10 μm. Fig. 151. Irregular false pseudoloculi, basal layer with a single poroid areola occluded by a simple raised cribrum; scale bar = 1 μm.