These diatoms exhibit isovalvar, isopolar, and bilaterally symmetrical frustules that can take on different shapes when viewed from the valve, including lanceolate, linear, or linear-elliptical. The striae on the valve can be parallel, uniseriate, or radial, and they are lined with linear areolae. These areolae are occluded by hymenes at their inner apertures, forming straight or curved longitudinal lines.The diatoms have a narrow axial area, and the raphe sternum internally features a continuous longitudinal rib on one side, known as the primary side. The central area is usually plain and may be circular or rectangular, with internal thickening linked to the longitudinal rib within the raphe sternum.The raphe itself is straight, with various endings at the center, including straight or hooked externally and simple straight internally, with hooked terminal fissures. The girdle is made up of plain, open bands, with the first band being the widest.Each diatom cell contains two plate-like chloroplasts, each located on one side of the girdle, typically with a single elongated pyrenoid, which is visible when observed from the girdle.