The study by scanning electron microscope of the scolex of Cotugnia polyacantha, Raillietina (R.) echinobothrida, R (R.) tetragona, R. (R.) tunetensis and R. (Skrjabinia) cesticillus allowed us to demonstrate the presence, on the rostellum of each individual, of scale-like spines. We believe that these scale-like spines represent a new character of diagnosis for the whole of the Davaineidae.