These organisms form straight chains that are typically short and not twisted. The individual cells have an elliptical valve surface and apical axis. The valves themselves are either flat or slightly raised in the center and possess a prominent valve mantle, along with a small but discernible notch at the point where they meet the girdle. In resting cells, the girdle-band zone is relatively small. Setae, which are hair-like structures, arise from the cell corners and lack a basal part. The apertures are exceedingly narrow and resemble slits. Within these chains, there are two types of setae: thin setae, which are more or less curved, often straight, and typically slightly turned toward the chain’s ends; and heavy setae, which are almost club-shaped, increasing in thickness from the base outward and then thinning near the ends. The first two-thirds of the setae are almost straight and form a sharp angle with respect to the chain axis, gradually turning at an obtuse angle toward one end or the other and running almost parallel to the chain axis in the outer part. The thicker setae are distinctly angular and have small, spirally arranged teeth on their corners. Terminal setae are consistently thin and differ from the others in their positioning: initially forming a U-shape and then running almost parallel to the chain axis in the outer part. The number of pairs of heavy setae in a chain varies and doesn’t appear to follow a specific pattern. Each cell contains one chromatophore, situated on the girdle side. Resting spores have not been observed.