About the Dragonfish

For 18th century sailors, looking out on a vast, mysterious ocean, the sight of a serpentine creature breaking the surface might conjure up visions of dragons or mermaids. But try as they might, these mythical creatures remained tantalizingly out of reach.

It wasn’t until 1877 that scientists pulled up a real-live dragon from the North Atlantic, later dubbed the “ribbon sawtail fish” by the German naturalist Wilhelm Peters. Others were found in 1890 and 1906, and categorized together as dragonfish. Far from the fearsome, man-eating creatures sailors had described, these fish measured no more than 20 inches. But their long, transparent fangs and gaping jaws made them scary enough. With a slender, luminous barbel hanging from the females’ chins and glowing blue-green lights covering their bodies, this species is downright otherworldly.

Because only female dragonfish migrate to the ocean surface at night to feed, it took scientists longer to identify male members of the species. Size varies, but in general, males are much smaller than females. They don’t share the distinction of a glowing barbel, though other parts of their bodies sport light-producing organs called photophores. The male’s skeleton is made of cartilage, rather than bones, and they have no digestive system to speak of. That’s probably why male dragonfish also lack teeth—unlike the female, whose fangs are embedded with nanocrystals that make her bite even stronger than that of a shark. Instead of bothering to find food, male dragonfish remain in the twilight zone, playing flashlight tag with females.

Quick Facts

Common NameDragonfish
Scientific NameIdiacanthus sp.
Other NamesBlack dragonfish, ribbon sawtail fish, Pacific blackdragon
SizeFemales up to 53 cm (20 inches); males of different species are 5-15 cm (2-6 inches)
DiscoveryW. Peters, 1877 (Idiacanthus fasciola, or ribbon sawtail fish)
Eats what?Other fish
Eats how?Females travel to surface waters at night to snap up fish with strong fangs. The luminous barbel hanging off the chin may attract prey or help them see it.
Is eaten by?Other fish