(Haeckel, 1887)
Parmal meshes 400-500; in center of each plate a cross of four very large pentagonal or roundish aspinal pores, and around this a circle of 16 to 20 much smaller irregular, polygonal, coronal pores; latter about same size as sutural pores. On each condyle one thin zigzag-shaped accessory spine, nearly as long as radius. Twenty radial spicules very long, quadrangular, prismatic; on inside thinner and smooth, on outside thickened, with four rows of recurved teeth, serrated. Diameter of the shell: 0.18 mm, aspinal pores: 0.02 mm, other pores: 0.002 to 0.01 mm, bars: 0.003 mm.