Frustules araphid, elliptical to linear in outline and with rounded to capitate apices. Valves symmetrical to apical and transapical axes, with costa extending across the face. Labiate process (referred to as a "jelly pore" in the older literature) evident as a thickened area at one end of the valve. Intercalary bands few to many. Cells occur in zig-zag or straight filaments, formed by mucilage exuded through pore fields at the apices.
Light Microscope Image(s)
Each image is accompanied by the genus and species, California Academy of Sciences slide number (ie. CAS 612010), location of the specimen on the slide, and dimension in microns.