Haeckel, 1879
Central shell ellipsoidal, less often spherical, surface smooth, sutural furrows conspicuous. Secondary spicules almost as long as pyramidal main spicules, pin-like, curved. Cornets bell-shaped, surrounding main spicules to about half their length; clearly delimited from central shell; twice as broad at distal end as at the base; surface covered by many (>16) ribs which extend into small thorns at edge of cornet. Length of main spicules: 0.08 mm; secondary: 0.05 mm; diameter of central shell: 0.04 mm; length of cornets: 0.03 mm.