Frustules biraphid, heterovalvate. Asymmetrical to the transapical axis and symmetrical to apical axis in valve view, flexed about transapical axis in girdle view. Concave valve with raphe almost extending length of valve; convex valve with short raphe branches near apices only, sometimes difficult to discern. Raphe straight, proximal ends dilated. Cells can be found free or attached by mucilage stalks.
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.