Entamoeba hartmanni

Entamoeba histolytica and Entamoeba hartmanni. Trophozoites in fecal smear (trichrome stain, oil immersion). A much smaller trophozoite of E. hartmanni is readily visible near a trophozoite of E. histolytica. Note the lighter staining cytoplasm of the E. hartmanni trophozoite and its smaller nucleus with a punctate karyosome; the trophozoite of E. histolytica takes a darker stain and its nucleus is larger and more difficult to see.