Hymenolepis (now Rodentolepis) nana
Rodentolepis nana (formerly Hymenolepis nana), adult
Rodentolepis nana, also known as the dwarf tapeworm, is a small intestinal worm that parasitizes rodents and humans. Adults measure 15 to 40 mm in length are comprised of multiple small proglottids that are wider than they are long. Rodentolepis nana adults are infrequently submitted to the clinical parasitology laboratory; when received, they were usually obtained during colonoscopy where they were an unexpected finding.
Rodentolepis nana, eggs
Rodentolepis nana, commonly known as the dwarf tapeworm, produces oval-shaped eggs with inner and outer membranes. The inner membrane has 2 poles (arrows) from which 4 to 8 polar filaments arise and spread out between the membranes. Within the inner membrane is the embryo (onchosphere) that contains 6 hooks. The eggs are smaller than the eggs of Hymenolepis diminuta, measuring 30 to 50 micrometers in greatest dimension.
