(Genus):Dorsal spines 2. Body naked. Four lateral lines, photophores associate with all lateral lines. Pectoral axilla smooth, without pore and ovate glandular tissue. (Species):Branchiostegal photophore series restricted mid-ventral, with deep U-shaped apex anteriorly. Margin of soft dorsal fin membranes with black blotches, black margin intermittent.
Distribution:
Virginia of the North America to central Brazil southwards. The present species lives relatively shallow water, less than 100 fathoms.
Remarks:
The present species closely resembles to P. bathoiketes, but both are distinguishable by coloration of the margin of soft dorsal fin membranes awd habitat (P. plectrodon has intermittent black margin of soft dorsal fin membranes and shallower habitat). P. porosissimus, a sibling species of the present species, distributes from southern Brazil to Argentina. (Shimizu)