Lecythium is a shelled amoeba, with an organic shell. This phase contrast image is of the pseudopodia as they spread across the microscope slide. From a freshwater pond in Idaho.
Pseudodifflugia, a testate filose amoeba. These are small species with a chitinoid ovoid or spherical test covered with quartz particles. Difflugia are generally larger and have lobose pseudopodia. Pseudodifflugia feeds on diatoms and other algae. From freshwater koi pond near Boise, Idaho. Phase contrast.