フロリダ半島近海からアンチル諸島の水深330〜1,240mには,本種にごく近縁のN. cursor A. Milne Edwardsが分布している。額角先端が水平に細く突出し,また,第5腹節の側甲の後端がちょうど直角をなし,小さなとげに終っている。
Diagnostic characters:
Characteristic in having the remarkably long posterior three pairs of pereiopods; body slender and cylindrical as a whole; carapace only with very shallow cervical groove; antennal and branchiostegal spines distinct. Rostrum short, about one-third as long as carapace, and not tapering distally; 12-17 small teeth on upper margin, and lower margin with a fringe of long hairs and a subterminal spine. Postrostral carina extended back onto median part of carapace. Abdomen about twice as long as carapace, the third segment being convex dorsally; fourth to sixth segments with dorsal blunt carina.
Distribution:
Previously known from the Gulf of Mexico and the Antilles, 700-1,570 m deep.
Remarks:
The close congener, N. cursor A. Milne Edwards is also distributed in the West Atlantic from Florida to the Antilles, 330-1,240 m deep, but readily distinguished from this species by having the horizontal rostrum with a sharp tip and by the pleura of the fifth abdominal segment armed with a spinule.