Common name: Smooth Dreamer

Author: Keely Cook

Scientific name: Chaenophryne draco

Size range: Between 12cm and 1m. (Generally the size of a teacup.)

Identifying Features

Known as “Ugliest creature identified,” the Smooth Dreamer has a massive head with a gigantic, crescent-shaped mouth that is filled with sharp, translucent teeth angled inwards to prevent prey from escaping. Smooth Dreamers have roughly 25-51 teeth in the upper jaw and 33-53 teeth in the lower jaw. They are a dark grey to a dark brown in colour, blending in with the dark depths of the sea. The Smooth Dreamer has small eyes which are adapted to reflect blue light, but generally use their sense of smell for navigation. It is easy to differentiate males from females because the females have a long dorsal spin with a luminous ball of flesh between the eyes, which gives off a blue-green glow to lure prey in. When the “ball” of light is touched, the jaw opens by reflex, letting in prey unsuspectingly before the jaws snap shut. The males are born with olfactory organs that can detect the scent of females whom they can mate with. Running along the body of the Smooth Dreamer are a series of rays that rest above the pectoral fins. The pectoral fins resemble a hand, which makes the fish look like it’s “wobbling” instead of swimming normally.

Habitat

The Smooth Dreamer is found off the coast of Vancouver Island and along the entire coast of North America and Australia. It makes its home down from 350 to 1750 meters (3000 feet) deep. They have adapted to living under the extreme pressures of the deep that contain no light.

Prey

The Smooth Dreamer is well-adapted for living in the depths. Its dorsal spine, tipped with a luminous ball of flesh, attracts prey. It is a carnivorous creature whose mouth can stretch to consume prey up to twice their size. They are constantly floating, almost motionless, in the water. The only movement they are making is swinging their ball of light back and forth. They are adapted to not feed every day because it is difficult to find prey at their depth. Adult males might become parasites to the females as they mature.

Predators

There are no true predators for the Smooth Dreamer. Occasionally, and cod or a congler may pose a threat the fish if it is large enough, but the only creature that eats the Smooth Dreamer regularly are humans. Smooth dreamers avoid predators by using bioluminescence as a decoy, being dark colours, or they remain floating, nearly motionless. It is not known if the Smooth Dreamer is venomous.

Life Cycle

It is not known if this particular species of Anglerfish is parasitic. When a male begins to mature, its digestive system begins to degenerate. The male will die if it does not find a female before it fully matures. When the male senses a female, using its olfactory organs, it latches on to the female with its teeth, secreting an enzyme that fuses the fish together. Once the male and female are fused, the male loses its eyes and almost all of its internal organs, becoming only a source of sperm for fertilization. The male becomes a parasite and the female can have up to six males fused with her. When the female is ready to spawn, she has a mate instantly available. She lays the eggs in a thin sheet of gelatinous material about 9 meters by 1 meter. This sheet floats along in the sea until the eggs hatch into tiny larvae. Juvenile Smooth Dreamers are planktonic, with noticeably larger fin rays. The larvae swim to the surface and feed on the plankton and as they begin to mature, then they return to the bottom of the sea.  Some types of Anglerfish are not parasitic and live their lives as mates. It is not known how long the Smooth Dreamer’s lifespan is because scientists have not been able to keep one alive for more than 3 years in captivity. This is because the Smooth Dreamer lives at a depth with such immense pressure that they are not able to replicate it.

Photograph by D. Young (specimen provided by Archipelago Marine Research Ltd.)

References

BBC Home (2005). Animal Fact Files, Anglerfish. Retrieved November 27th 2011 from http://www.bbc.co.uk/nature/blueplanet/factfiles/fish/angler_fish_bg.shtml

Hart, J.L. (1988). Pacific fishes of Canada: Fisheries Research Board of Canada

National Geographic (2011). Anglerfish. Retrieved November 24th 2011

from http://animals.nationalgeographic.com/animals/fish/anglerfish/

Royal BC Museum (2011). The Anglerfish. Retrieved December 7th 2011 from http://www.royalbcmuseum.bc.ca/Natural_History/Fish.aspx?id=294

Sea and Sky (2011). The Deep Sea Anglerfish. Retrieved November 24th 2011 from http://www.seasky.org/deep-sea/anglerfish.html