This #SundayFishSketch comes from Ichthyologist, Rene Martin. Visit her shop on InPrint to see more of her artwork or to order prints!
The Deep-Sea Dragonfish, a scaleless eel-like fish about 6 inches in length that lives (you guessed it) in the deep sea, specifically the bathyal zone of the Atlantic Ocean beyond where any light can reach.
As you get deeper in the ocean, the pressure builds tremendously as the amount of water above you increases. Dragonfish spend their time between 5000 feet and 15000 feet below the surface, though some will venture as deep as 16500 feet below—over 3 miles. The conditions at these depths are virtually unimaginable to us on the surface, with pressures reaching up to around 600 atm, or 600 times the amount of pressure at sea level.
Dragonfish have unique adaptations to deal with that craziness. Their skeleton is a minimalist dream, except for the jaw which remains somewhat complex. They have proportionally large, curved teeth, sometimes hinged, allowing their teeth to fold in when feeding. They also have a second set of jaws within what is basically the beginning of their throat, called the branchial basket.
But perhaps the most interesting characteristic of the dragonfish is their ability to produce light, both blue and red. They possess specialized organs called photophores which line their body as well as on their barbell, a fleshy extension like a fishing rod (think angler fish on Finding Nemo). This is a trait called bio-luminescence.
It uses its light spectacle to attract prey, usually other deep sea fish and invertebrates, luring them in before snapping their horrifying mouths around their bodies.