(Haeckel, 1887)
Skeletal spicules strongly flattened, two-edged; each spicule twice constricted outside the lattice shell, and tapering to a point. Strong apophyses twice forked, apophysal ends widening to form knuckle-like joints uniting with those from adjacent spicules to form fine-meshed and thick-beamed lattice shell. Diameter of shell: 0.11 mm, of large meshes: 0.04 to 0.05 mm, of small meshes: 0.01 mm; breadth of spicules: 0.01 mm.