The inner medulla is well-defined and can be up to three cells thick. The cortex consists of two layers of very small, rounded cells. The outermost epidermal cells are elongated and have a fiber-like appearance. The plants exhibit colors ranging from reddish to purple. They are erect and have a firm, cartilaginous texture, attaching to surfaces through a flat, disk-shaped holdfast. Branching occurs alternately, and the branches are fleshy and cylindrical, with spiny protrusions. In cross-section, the axial cells are small and rounded, surrounded by five periaxial cells. The medulla, cortex, and epidermal cells have the described characteristics.