(Schröder)
Diagnosis: Cell presumed to be originally spherical, but is later somewhat deformed, depending on materials incorporated into the skeleton. Central capsule ellipsoidal to spheroidal. Skeleton of encrusted detrital siliceous material. Individuals in Schröder’ s illustrations shown with a variable mixture of skeletons from diatoms, silicoflagellates, and polycystine radiolarians.
Diameter: 0.06-0.09 mm.