Bizarre alien-like animal wanders sea floor by night

This strange looking creature is an animal that lives on the ocean floor at various depths. It belongs to a group of animals that is one of the most numerous of the ocean animals, and also one of the most vital. It is a sea cucumber, commonly known as a worm sea cucumber. Although they come in different shapes and sizes, se cucumbers are similar in many ways. They move slowly or remain stationary on the ocean bottom as they filter debris and waste from the water and the sediment. They digest and process large volumes of debris over their lifetime, making the ocean cleaner and keeping it free from harmful bacteria that would overpopulate among the waste if they did not do their jobs.

Simple organisms, they possess no true brain. Their sensory ability and locomotion is controlled by a ring neural tissue. They generally have a sensitivity to light and to touch due to the scattering of nerve tissue along the outer surfaces. They move over the ocean bottom consuming the organic matter that has settled. Some of them feed the organic matter into their mouths using feathery appendages that draw in food toward the centrally located mouth.

This sea cumber measured approximately 2m (6 feet) in length, with a girth roughly equivalent to a large English cucumber. It was making its way along in the dark of night when it was seen by a scuba diver who was using lights to illuminate the reef as his group explored and recorded the nocturnal activity.
The ocean is a completely different world by night. Different animals become active under the cover of darkness, hunting by using their keen senses to locate prey that is less able to see them coming. As the sun sinks beneath the horizon, many animals seek shelter, hiding among the coral and rocks. The animals that emerge from hiding are strange and fascinating. They move easily in the darkness, gathering food and avoiding becoming food. For scuba divers, exploring the darkness is intimidating and enthralling at the same time. It is a world of eerie silence and great beauty at the same time.