Dipylidium caninum

Dipylidium caninum. Scolex of adult tapeworm (carmine stain, high power). The adult tapeworm of this species is a common parasite of dogs but occasionally infects humans, especially children. The tapeworms may attain lengths of 10 to 70 cm. As seen here, the scolex has four large suckers and a conical rostellum bearing multiple rings of small spines.