Pacific viperfish

Pacific viperfish
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Stomiiformes
Family: Stomiidae
Genus: Chauliodus
Species: C. macouni
Binomial name
Chauliodus macouni
Bean, 1890

The Pacific viperfish, Chauliodus macouni, is a predatory fish that lives in the abyssal depths of the deep sea. In daytime it can be found from 200–5000 m below the ocean surface. At night it swims up into shallower depths of less than 200m where food is more plentiful. Pacific viperfish will mostly eat crustaceans and small fish. They typically reach lengths of up to 1 foot and are considered an example of deep-sea gigantism. It is believed that its first dorsal fin's photophores are used to attract prey. 

Pacific viperfish can be characterized by its large mouth, long fang-like teeth and long dorsal fin ray (as much as half its body length). They are iridescent dark silver-blue color in life with pale fins. They can also be a light black color with blue fins.

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