Dibothriocephalus latus
Dibothriocephalus (formerly Diphyllobothrium) species, eggs
The eggs of Dibothriocephalus species are oval with a thin colorless shell, a non-shouldered operculum, and a small knob at the opposite (abopercular) end. Of the operculate eggs seen in human stool specimens, Dibothriocephalus eggs are in the intermediate size range, measuring 55 to 75 micrometers long by 40 to 50 micrometers wide.
Dibothriocephalus, adult, proglottids, macroscopic
The proglottids of Dibothriocephalus species are broader than they are tall, thus earning this worm the name "broad fish tapeworm." Note that the rosette-shaped uterus is often visible as a dark structure in the center of each proglottid. Images courtesy of Phong Duong.
Dibothriocephalus, adult, proglottids, microscopic
These images show mounted and stained Dibothriocephalus sp. proglottids. Note the characteristic "rosette-shaped" uterus with characteristic operculated eggs.