The cells are roughly square in shape, with their width being nearly equal to their length. They have 10 to 25 setae, which extend at right angles to the chain axis. These setae typically have a shorter basal portion compared to those found in B. delicatulum. The apertures on these cells are small, and the terminal setae have fine spines arranged in spiral rows. The cell diameter measures between 30 to 36 µm. The terminal setae first extend perpendicular to the chain axis and then sharply curve obliquely toward the chain in their outer section.