Protists
Members of this kingdom include most members who cannot be classified as plants, animals, or fungi. They are eukaryotic organisms and are nearly all unicellular.
Pyrrophyta
Pyrrophyta are also commonly known as dinoflagellates. They are a large group that form the phylum dinoflagellata. Most are marine organisms, however many are found in freshwater as well. Most dinoflagellates are phototrophic, however some are known to be mixtrophic as well. One example are the zooxanthellae, a very common dinoflagellate.
Chrysophyta
Phylum Chrysophyta contains the groups of the diatoms as well as the gold, brown, and yellow algaes. Diatoms are one of the most common phototrophic, unicellular organism within the marine ecosystems. A unique feature of diatom cells is that they are enclosed within a cell wall made of silica called a frustule. These frustules are almost always bilaterally similar and are especially sought after.
Sarcodina
Sarcodina is the largest phylum of the subkingdom protozoa. Two organisms of this phyla are the radiolarians and the foraminiferans. The Radiolarians are a group of organisms that produce intricate mineral skeletons, typically with a central capsule dividing the cell into the inner and outer portions of endoplasm and ectoplasm. They are heterotrophic. (Left Image)
Foraminifera (forams for short) are single-celled protists with shells. Their shells are also referred to as tests because in some forms the protoplasm covers the exterior of the shell. The shells are commonly divided into chambers which are added during growth, though the simplest forms are open tubes or hollow spheres. Depending on the species, the shell may be made of organic compounds, sand grains and other particles cemented together. (Right Image)
Foraminifera (forams for short) are single-celled protists with shells. Their shells are also referred to as tests because in some forms the protoplasm covers the exterior of the shell. The shells are commonly divided into chambers which are added during growth, though the simplest forms are open tubes or hollow spheres. Depending on the species, the shell may be made of organic compounds, sand grains and other particles cemented together. (Right Image)