Polycystines

The polycystines are a group of radiolarians. They include the vast majority of the fossil radiolaria, as their skeletons are abundant in marine sediments, making them one of the most common groups of microfossils. These skeletons are composed of opaline silica. In some it takes the form of relatively simple spicules, but in others it forms more elaborate lattices, such as concentric spheres with radial spines or sequences of conical chambers. Two of the orders belonging to this group are the radially-symmetrical Spumellaria, dating back to the late Cambrian period, and the bilaterally-symmetr

Spumellaria is an order of radiolarians in the class Polycystinea. They are ameboid protists appearing in abundance in the world's oceans, possessing a radially-symmetrical silica (opal) skeleton that has ensured their preservation in fossil records. They are holoplanktonic, meaning they spend their whole lives classified as plankton. Spumellaria are globally distributed and a big part of our ocean’s silica biogeochemical cycle. Before diatoms, they were the main contributors to siliceous ocean sediments. They belong among the oldest Polycystine organisms, dating back to the lower Cambrian (ca

Nassellaria is an order of Rhizaria belonging to the class Radiolaria. The organisms of this order are characterized by a skeleton cross link with a cone or ring.

Collodaria is a unicellular order (organisms within the order are called Collodarians) under the phylum Radiozoa (or Radiolaria) and the infrakingdom Rhizaria. Like most of the Radiolaria taxonomy, Collodaria was first described by Ernst Haeckel, a German scholar who published three volumes of manuscript describing the extensive samples of Radiolaria collected by the voyage of HMS Challenger. Recent molecular phylogenetic studies concluded that Collodaria contains three families, Sphaerozodae, Collosphaeridae, and Collophidilidae.

Actinommidae is a family of radiolarians.

Collozoum is a radiolarian genus formerly reported in the subfamily Sphaerozoidae, now reported descending from the order Collodaria. The genus contains bioluminescent species. It is a genus of colonial radiolarians (as opposed to solitary).