Argyropelecus aculeatus, the lovely hatchetfish or Atlantic silver hatchetfish, is a species of fish in the family Sternoptychidae.

[1] It may exceed 70 millimetres (2.8 in) standard length (SL).

It lives in the mesopelagic zone of all oceans and performs diel vertical migration.

[2] A. aculeatus feeds on a large range of prey items; in the Gulf of Mexico ostracods and copepods dominated the diet of small individuals (<30 mm SL) and euphausiids, molluscs, and fish the diet of larger ones.

[3] The silvery coloration and bioluminescence of the lovely hatchetfish allows it to hide from predators and prey in the down-welling light of the twilight zone.