A black dragonfish

A Black Dragonfish is very long and very thin fish that lives in the deep water and will go as low in the water as about 2 thousand feet. They live in mesopelagic to bathypelagic waters at depths of about 2,000 m.

This species presents one of the most extreme cases of sex**l dimorphism known. The female is maximum of 40cm long, with small eyes, chin barbell and long fang-like teeth, which are used for catching its primary food item - other fish. The male is just 5cm and has no teeth, no chin barbel, a non-functional gut, and is dark brown rather than black.

The Black Dragonfish has a very unique ability. Like a lot of fish who live in the deep ocean or sea, it can make its own headlight.