Haeckel, 1887
Shell ovoid, very thick-walled, dark, opaque. Two main spicules slightly to 1 1/2 times longer than other 18. Cornets around spicules almost reaching spicule ends, with several longitudinal keels, their edges with strong spines. Shell diameter: 0.08-0.1 mm; main spicules: 0.05-0.06 mm.