These are unicellular and characterized by cells divided into two symmetrical halves, known as semicells. Each semicell typically bears an unbranched spine at its angles. The cell wall is smooth and lacks ornamentation except for pores or fine granules. A single chloroplast is present within each semicell. The distinguishing features among Staurodesmus species include variations in cell shape, as well as differences in the size and orientation of the spines. These characteristics help differentiate one species from another within the genus.