Frustules biraphid, valves asymmetrical to apical axis, symmetrical to the transapical axis, linear to linear-lanceolate in shape with protracted to capitate apices. Frustules with raphe system marginal, on same side in both valves. Fibulae distinct, striae with fine puncta.
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.