Paulinellidae De Saedeleer 1934, emend. Adl et al. 2012
Diagnosis: Pyriform, uncompressed shape; scales, when present, long, with length perpendicular to aperture. At least two genera (Ovulinata, Micropyxidiella ) with totally organic test without silica scales.
Raphidocystidae Zlatogursky, 2018 Diagnosis: centrohelids with monolayered plate-scales covering cell surface. Plate-scales with a hollow inflected margin. Sometimes trumpet-shaped or tubular spine-scales present, forming an