Entamoeba histolytica / dispar
Entamoeba histolytica / dispar cysts stained with iodine from an infected olive baboon, Papio anubis. The cysts of Entamoeba histolytica and Entamoeba dispar are considered morphologically indistinguishable. Mature cysts are spherical, have 4 nucleii, and measure 12 to 18 µm in diameter.
Lesion of Entamoeba invadens in the stomach of a tortoise. Lesions typically occur in the intestinal tract and liver, creating ulcers characterized by hyperemia, inflammation, and an infiltration of neutrophils. Amebae are found at the periphery of the ulcer, leaving the cavity filled with necrotic tissue