Description
Centroheliozoa with a periplast comprising one or several types of tangential , spindle-shaped or flat , siliceous scales , which have a reticular or smooth upper surface and a hollow marginal rim . There are no internal septae . Radial elements absent. Five species from marine and freshwater habitats. References: Durrschmidt and Patterson (1987b), Siemensma and Roijackers (1988b) ; Mikrjukov (1996b) for taxonomy . sca le , and a scheme of the scale of Raphidiophrys (aft er Siemensma 1991) .
Type species
Polyplacocystis symmetrica (Penard , 1904) Mikrjukov , 1996
Figures
Polyplacocystis symmetrica (after Siemensma, 1991) and a typical scale.
Raw text
Centroheliozoa with a periplast comprising one or several types of tangential , spindle-shaped or flat , siliceous scales , which have a reticular or smooth upper surface and a hollow marginal rim . There are no internal septae . Radial elements absent. Five species from marine and freshwater habitats. References: Durrschmidt and Patterson (1987b), Siemensma and Roijackers (1988b) ; Mikrjukov (1996b) for taxonomy . sca le , and a scheme of the scale of Raphidiophrys (aft er Siemensma 1991) .