Family: Body long, flat, with beak-like anterior rostrum; oral area in long ventral groove
behind rostrum Müllerian vesicles in endoplasm.
Genus: Oral area round, behind rostrum, leads into tubular cavity (Illustrated Guide, 1985).
Species (magnus Stokes): Extended about 700 μm long; dark brown; twelve to twenty or more
Müllerian vesicles in a row along
dorsal border (Kudo, 1966).