Pacific Viperfish
Chauliodus macouni
- Least concern
- Card rarity: Common
- Fish

The Pacific viperfish (Chauliodus macouni), is a predatory deep-sea fish found in the North Pacific. It is reported as being either mesopelagic or bathypelagic, with diel vertical migration to shallower waters. The Pacific viperfish is one of the nine different species that belong to the genus Chauliodus, the viperfish. The Pacific viperfish tend to be the largest of the species, typically reaching lengths of up to 1 foot and are considered an example of deep-sea gigantism. The length-weight relationship of the pacific viperfish varies with sex with females tending to be longer and heavier than males.
Classification
- Class
- Actinopterygii
- Order
- Stomiiformes
- Family
- Stomiidae
- Genus
- Chauliodus