Haeckel, 1860
Central shell ellipsoidal, small, thick-walled, sharply set off from cornets. Cornets conical, thin-walled. Main spicules cylindro-conical, with longitudinal keels. Secondary spicules 2 times shorter than main, strongly compressed. Length of main spicules: 0.1 mm; secondary: 0.05 mm; diameter of central shell: 0.03-0.04 mm; length of cornets: 0.05-0.06 mm.