Sternoptychidae

Pacific hatchet fish

Argyropelecus affinis

Migrating between depths day and night

• Silver
• Northern Hemisphere
• Regional distribution
• Marine fish
• Atlantic Ocean
• Indian Ocean
• Pacific Ocean
• Africa
• East Asia
• North America
• Deep-bodied
• Small

Argyropelecus affinis is a species of ray-finned fish in the family Sternoptychidae, described by Garman in 1899, found in the tropical and subtropical Atlantic, Indian and Pacific Oceans. Common names for this fish include Pacific hatchetfish, deepsea hatchetfish and slender hatchetfish. It inhabits the upper mesopelagic zone between 350 and 600m during the day, and between 100m and 350m during the night and is either non-migratory or performs short daily vertical migrations.