Anterior face of the obturaculum of an adult has a thick crust with a central, laminate, fin-like structure arising from between the obturacular halves, apparently secreted by the medial margins of the obturacular halves. The worms were fixed in their tubes, with a deep cleft between the obturacular halves, suggesting the obturacular region is broadly spread when protruding from the tube in life. There are two kinds of filaments associated with the obturaculum, restricted to distinct regions. The distal, larger, sensory filaments are fused into paired lamellae at about 75% of the obturacular length from the base. The remainder of the proximal obturacular region with 30-35 pairs of lamellae composed of smaller, branchial filaments, with pinnules. The mid-region of the obturacular halves are laterally compressed, and are flattened ovals in transverse section, lacking a dorsal groove and ventral ridge. There is a single medial excretory pore opening from a pronounced, dorsal medial ridge at the base of the obturaculum. The anterior margin forms a modest sheath around the base of the obturaculum. The posteroventral margin of the vestimentum is entire. The opisthosome is unknown. The tube is smooth, brown-buff in colour, lacking collars and is tapering. The tube is extremely hard and rigid.

(Jones, 1985)

Florida Escarpment, Gulf of Mexico, 3,268-3,270 m depth (Jones, 1985)