The group includes many genera which are internal parasites or commensals of animals: for example "Entamoeba" and "Endolimax". Some are human pathogens, causing diseases such as amoebic dysentery. Other genera of archamoebae live in freshwater habitats, and have flagella. Most have a single nucleus and flagellum, but the giant amoeba "Pelomyxa" has many of each.