Basic Information:

  • Hymenolepis belongs to the cestode class.

hymenolepis nana hymenolepis diminuta

(images courtesy of CDC Division of Parasitic Diseases) http://www.dpd.cdc.gov/dpdx/HTML/Hymenolepiasis.htm

note: The difference between the eggs is used for diagnostic purposes. The H. nana egg has polar filaments that project from either side of the inner membrane, which encompasses the oncosphere. These polar filaments are not found in the H.diminuta egg.

Another key difference is found in the adult morphology. The scolex of H. nana has a rostellum equiped with hooks, while the scolex of H.nana does not have these hooks on its comparatively small rostellum. This difference is representative of the different stages and the different types of development that these worms undergo inside of a human (or other difinitive) host.

  H. diminuta scolex
(courtesy of Micrographia) <http://www.micrographia.com/specbiol/helmint/platyhel/cest0100/hymenol2.htm>


courtesy of College of Biological Sciences at Ohio State University <http://www.biosci.ohio-state.edu/~parasite/hymenolepis_diminuta.html>




H. nana scolex

  (courtesy of The Korean Soceity of Parasitology <http://www.atlas.or.kr/atlas/alphabet_view.php?my_codeName=Hymenolepis%20nana>