View data on catalog of fishes here.
Dorsal-fin rays 11–13, usually 12. Anal-fin rays 29–31. Pectoral-fin rays 9–10. Vertebrae 45–46, including 20 anal vertebrae. Gill rakers 6 + 12. Pyloric caeca 7–8 (based on 6 specimens). Peritoneum black, vent edged by dark ring. SL 4.1–4.6 times greater than head length, decreases with growth. Eye diameter approximately equal to width of interorbital distance. SL 6.4–7.1 times greater than body depth, decreases with growth. Photophores: OV and VAL on same level: VAL and VAV 9 each; anterior 2 AC or only 1 of them is slightly raised, AC 23–25, including 16–17 above anal fin.
Known only from two seamounts of the Sala-y-Gomez Ridge and Southeastern Pacific. "Parin N, Borodulina O. 1990. Survey of the genus Polymetme (Photichthyidae) with a description of two new species. Voprosy Ikhtiologii 30(5):733–743."
The following morphologic description of the genus is based on Parin and Borodulina (1990). Body elongate, vertebrae 42-46. Eye normal. Mouth large, two rows of premaxillary teeth. Branchiostegal rays 13–14. Gill rakers 15–19, typically 16 to 18. Dorsal-fin rays 10–13 (14), Anal-fin rays (25) 27–34. Pectoral-fin rays 9-11. Pelvic-fin rays 7. Pelvic fins far anterior to the dorsal-fin origin. Origin of anal fin below the end of the base of the dorsal fin. Adipose fin present. Photophores: ORB 1, by the anterior margin of the orbit. OP 3. SO 1. BR 9–10. IV 21, 10th slightly raised; VAV 8–9; AC 22–25, of them, 15-19 above the anal fin, anterior 2 may be slightly raised; IC 50–54. OV 9; VAL 8–9, anterior 1 or 2 may be slightly raised; OA 17-18.
Greatest length 209 mm.