The Radiolaria, also called Radiozoa, are unicellular eukaryotes of diameter 0.1–0.2 mm that produce intricate mineral skeletons, typically with a central capsule dividing the cell into the inner and outer portions of endoplasm and ectoplasm.

radiolarian, any protozoan of the class Polycystinea (superclass Actinopoda), found in the upper layers of all oceans. Radiolarians, which are mostly spherically symmetrical, are known for their complex and beautifully sculptured, though minute, skeletons, referred to as tests.

Radiolarians species, members of the subclass Radiolaria, are single-celled eukaryotes commonly found in marine environments (with some being colonial). Although some of the species are restricted to a specific region, these organisms are widely spread in major oceanic ecosystems across the world.

Radiolaria are well known for their paleontological signatures, but little is known about the ecology of modern assemblages. They are found from polar to tropical regions, in the sunlit layers of the ocean down to the deep and cold bathypelagic.

Radiolaria is a diverse grouping of amoeboid protozoa that produce intricate mineral skeletons, typically with a central capsule of cytoplasm separating the cell into inner and outer cytoplasmic portions, called endoplasm (with nuclei) and ectoplasm (or extracapsulum).

Radiolaria are holoplanktonic protozoa widely distributed in the oceans. They occur throughout the water column from near surface to hundreds of meters depth. As with many planktonic organisms, their abundance in a geographical region is related to quality of the water mass, including such variables as temperature, salinity, productivity, and ...

Radiolaria are holoplanktonic protozoa and form part of the zooplankton, they are non-motile (except when flagella-bearing reproductive swarmers are produced) but contain buoyancy enhancing structures; they may be solitary or colonial.

Radiolaria are unicellular holoplanktonic protozoa with siliceous or strontium sulfate skeletons. Mainly studied by micropaleontologists because of their excellent fossil record, they are also key members of planktonic communities and play important roles in various oceanic ecosystems.

Radiolaria are free-living marine pseudopodbearing protozoans characterized by (1) a radiating network of slender pseudopodia, (2) an organic “central capsule membrane” within the cytoplasm, and (3) a skeleton composed of transparent glass (opal) with or without organic inclusions or of crystalline strontium sulfate (celestite).

Radiolarians are single-celled protozoa, measuring less than 0.1 – 0.2 mm in diameter, that produce intricate shells (skeletons) of amorphous silica. They float as part of the zooplankton in the first 200 meters of water in the Earth’s oceans (photic zone).