This species differs from its congeners in having the following set of characters: male postorbital photophore (PO) large, 26.8-39.9% upper jaw length (UJL), in specimens greater than 60 mm (vs. small to moderate, 7.8-28.1% UJL, in all its congeners except P. atrox); female PO moderate, 10.3-15.0% UJL, in specimens greater than 60 mm (vs. small, 6.1-11.1% UJL, in P. tantillux and P. goodyeari); male AO small, 2.4-4.7% UJL, in specimens greater than 60 mm (vs. large, 4.9-9.6% UJL, in P. tantillux and P. atrox); three tooth patches positioned at posterior end of the first, second, and third basibranchials (vs. two basibranchial tooth patches in P. guernei); total dorsal- and anal-fin rays 49-55, rarely 47, 48, or 56 (vs. 57-63, rarely 56, in P. goodyeari); females maturing at a small size, approximately 60 mm (vs. greater than 100 mm in P. atrox and P. liemi) (Ref. 80463).