Systematic Position

The membraneous integument and the lack of dermal photophores place these specimens in the "S. japonicus" group of the subgenus Sergia. The absence of an ocular tubercle and the fact that the cornea is barely wider than the ocular peduncle distinguishes it from S. tenuiremis, S. kröyeri and S. laminatus; the distinctive rostral profile distinguishes it from S. profundus and the branchial formula from S. inous.

The Cook Strait specimens agree in every way with the numerous descriptions and figures of the North Atlantic S. mollis Smith, which has been shown to be synonymous page 24with S. japonicus Bate taken by the Challenger Expedition off Japan (see Hansen, 1896, 1903; Burkenroad, 1940).