Quoy and Gaimard, 1834
Gastrozooid with main axis up to 1.5 mm long, with few gill-slits (up to 13), digestive tract U-shaped, anus located dorsally to the esophageal funnel. Both phorozooids and gonozooids with short endostyle from M2 to M4. Neural ganglion at M33/4. Gill-septum strongly arched, extending dorsally to M2 and ventrally to M3, its posterior bend extending to M53/4. Ovary at the intestinal coil. Testis club-shaped, elongate in the antero-posterior axis, dorsal to the digestive tract, opening at M6 and extending forward to M2. Gonozooids up to 10 mm long.