Long rhinophore rising from low sheath with tuberculated rim (1) ; base smooth (2), upper lamellated part with 18 lamellae (3) at body length 11mm and 13 lamellae (4) at body length 6mm.
Left and right lamellae meet at anterior groove (5) and as posterior ‘V’ (6). Translucent, coloured as mantle. Lengths of animals: left & right 11 mm Menai Strait; centre 6 mm N. Yorkshire.