Shell thick-walled, ellipsoidal, surface covered with circular aspinal pits with oval aspinal pores, edges of pits protruding, forming sheaths with serrated crests. Bases of spicules also surrounded by sheaths, equally large or nearly so, extending to 1/4-1/3 of the spicule length; sheaths around main spicules better developed than those around secondary ones; sheath rims producing long pin-like accessory spines. Within sheath, two opposing ribs extend from narrower edges of spicules, dividing aspinal pit into 2 parts, with 1 aspinal pore in each. Aspinal pits surrounded by 8-12 smaller sutural pits; all pits bordered with small, pin-like accessory spines. Diameter of shell (excluding spicules): 0.12 by 0.11 mm; length of equatorial spicules: 0.11-0.13 mm, polar: 0.11 mm, secondary: 0.09 mm.