CESTODES

  • Cestodes belong to the phylum Platyhelminthes of the larger animal kingdom and are more commonly known as flatworms. Members of this phylum do not have a respiratory or circulatory system and the majority are parasitic. However, some free-living species are found within the class Turbellaria.
  • Cestodes a.k.a. tapeworms are made up of two parts: a scolex and a strobila. The strobila consists of a series of connected proglottides with the most posterior gravid segments equiped with both female and male reproductive parts. The structure of the scolex varies among the different species in this class but, generally, it consists of four peripheral suckers surrounding a centrally placed rostellum.
  • All cestode species are parasitic and require an intermediate host to complete their life cycle except for Hymenolepis nana. Characteristic of species found in this class are thier lack of complete digestive systems. As a result, all adult cestodes reside in the small intestine of their hosts.
  • Other common cestodes include D. latum, T. solium, and Echinococcus.

 

References
Myers, P. 2002. "Platyhelminthes" (On-line), Animal Diversity Web. Accessed June 04, 2005 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Platyhelminthes.html.
Markell, Edward et al. Medical Parasitology. Philadelphia, PA: Sanders, 1999.