Cells of C. cuspidata have been reported to be "obovoid to ellipsoidal" in shape, with sizes ranging from 5-12μm in length and 2-5 μm in width. A distinct tapered "tail" has been reported at the tips of cells, which is unique among Cyanophora. Cells have only 1-2 plastids. As with other Cyanophora species, no cell wall is present.