Enypniastes

Enypniastes is a genus of deep-sea sea cucumber that contains only one species, Enypniastes eximia. Its unusual look has earned it nicknames such as the headless chicken fish, headless chicken monster, Spanish dancer, swimming sea cucumber, and pink see-through fantasia.

The animal has webbed, fin-like structures at both its front and rear, allowing it to swim up from the seafloor and rise as high as 1,000 meters into the water column. This ability helps it find new feeding areas and escape predators. Its size ranges from 11 to 25 centimeters. Color depends on size: small individuals are bright pink, while larger ones are reddish-brown.

The body is semi-transparent, and its intestine is visible through the skin, especially after eating. The body is round and bulbous, with forked tentacles and a large sail-like structure at the front. It can also produce bioluminescence.

Enypniastes lives mainly in the ocean’s benthic zone and is found worldwide. It spends most of its time in the water column, only touching the seafloor to feed. The first sighting in Southern Ocean waters occurred in October 2018, when an Australian government team captured an image of E. eximia on a camera deployed near East Antarctica.

It feeds mostly on benthic sediment, using its tentacles to push food into its mouth. Feeding is quick—it stays on the seafloor for at most 64 seconds, which is usually enough to eat fully. As a result, it feeds in short, separate episodes.

For movement, it rows its anterior veil like an oar. When a current is present, it uses its tentacles to pull itself downstream. It also pushes itself along with its tentacles.