Class rhizopodea
The Rhizopoda are important aquatic and terrestrial protozoa at the base of food webs and thus provide a major link in the transfer of energy to higher order consumers. They are distinguished by their pseudopods, simple or branched, passing by wide bases into the general surface, never fine radial nor fusing into complex networks; skeleton absent or a simple shell, otherwise known as a test.
Foraminiferans
Foraminiferans are members of a phylum or class of amoeboid protists characterized by streaming granular ectoplasm that, like other things, is used for catching food commonly by an external shell or "test" made of various materials and constructed in diverse forms. The majority of them live on or within the seafloor sediment while a smaller variety are floaters in the water column at various depths. Dying planktonic Foraminifera continuously rain down on the sea floor in vast numbers, and their mineralized tests are preserved as fossils in the accumulating sediment.