The cells are cylindrical with a broadly elliptical to circular cross-section, forming long, slightly twisted chains. Valves within these cells are mostly flat, with a low mantle. Two types of intercalary setae are present: delicate, regularly spaced ones that can be challenging to observe under a standard light microscope, and occasionally, heavily silicified setae. The silicified setae are long, curved, and point toward the nearest end of the chain, becoming nearly parallel to the chain axis at the distal end. Apertures are elliptical to hexagonal, moderately wide, and slightly constricted in the center. The cells contain numerous small, plate-like chloroplasts crucial for photosynthesis.