Bonnevie, 1913
Body oval to barrel shaped, largely transparent. Mostly blackish visceral mass fills entire body. Small lateral footlobes coalesce in front, forming single lobe, fixed anteriorly. Posterior footlobe, small when present, pointed; all footlobes united. Median tubercle absent. Wings large, narrow at base, tapering toward free tips. Hook sacs very large, with large gold-colored hooks. When hook sacs invaginated, both body poles are rounded; when evaginated, forming two powerful arms, diverging from buccal cavity. Hooks, about 40 on each side, of different sizes, largest as long as 1/4 body length. Jaw replaced by lip of glandular cells, ventral to radula; lip forming bow across ventral side of proboscis at base of odontophore between hook sacs. Radula on large conical odontophore, formula 3-1-3, with about 12 transverse rows; teeth extremely large. Lateral radula teeth horn shaped, in some laterals basal plate obscure or absent. Median plate with blunt cusp and number of small denticles at free border. Young specimens with circular ciliated bands. Body length 10 mm.