Cosmarium dispersum Johnson 1895

    Cells medium size, length and width almost equal. Cells measure 42–49 µm length and 41–46 µm width. Cell margins gently undulated and often less distinct toward the apex. Apices truncated or slightly rounded and cells finely punctuated. Cells deeply constricted at the center, sinus deep and narrowly linear and isthmus 11–13 μm. Semicells semi-circular in shape with truncated end, elliptical in vertical view and circular in lateral view.