(Popofsky, 1904)
Four main spicules cylindrical, much longer and up to 3 times thicker than remaining 16, each with 7 myonemes. Central capsule spherical, compressed, very small and dark. Calymma poorly developed. Length of main spicules: 0.7-0.15 mm, width: 0.004 mm; length of secondary spicules: 0.33-0.48 mm, width: 0.002-0.003 mm; diameter of the central capsule: 0.06-0.09 mm.