Telescope Octopus - Unique Residents Of The Deep Sea
The telescope octopus is an elusive, deep-sea octopus that lives at depths of between 500 and 6,500 ft in tropical and subtropical regions of the Pacific and Indian Oceans. Scientifically named Amphitretus pelagicus, the species is approximately eight inches long, and its arms account for nearly half of its length. The telescope octopus is believed to be related to the glass octopus, which is another species of deep-sea octopus. Unlike most octopi that flit on the seafloor, the telescope octopus drifts with deep ocean currents. The species spends most of its life suspended in a water column rather than crawling on the seafloor. Remaining suspended in a vertical position, as opposed to swimming horizontally, makes the telescope octopus harder to detect by deep-sea predators.
Physical Appearance
The telescope octopus is a gelatinous transparent flesh, which makes it difficult to see without careful examination. This characteristic, which is also shared by the glass octopus, means that the telescope octopus does not cast shadows, which makes the species difficult to detect by predators. In addition to avoiding potential predators, its transparent body also enables the species to easily approach unsuspecting prey. The only visible body parts of the telescope octopus are its tubular eyes and digestive glands. The telescope octopus also has delicate webbing between its tentacles, giving it a distinct ghostly shape. The species also has white suckers along the length of its eight arms.
Optical Adaptation
The elongated tubular eyes of the telescope octopus pop out of its head, giving the species its unique name. Its eyes are positioned on elongated, movable stalks, and it is the only species of octopus that has rotating telescopic eyes. The glass octopus has eyes that protrude somewhat, but are less prominent than those of the telescope octopus. Its unique eyes give the species a distinct advantage in the deep sea, providing a wide peripheral vision that enables the telescope octopus to see both prey and predators with ease. Additionally, the telescoping eyes allow for continuous monitoring of the local environment at any given time.
Evolution of the Telescope Octopus
Scientists have relatively limited knowledge of this rare species of pelagic octopus. The evolution of its unique optical features also remains a mystery. Several scientists have speculated that the telescope octopus and its closely related gelatinous species live their entire lives in what is referred to as an arrested larval stage, which is also called neoteny. Similar to the larvae and hatchlings of many octopus species, the telescope octopus stays suspended in water columns and has a nearly transparent body. Scientists suspected that they have a niche similar to the glass squid, but a DNA analysis of the species revealed that its closest living relatives are the Pareledonegenus that inhabits the ocean floors of the Antarctic. It is believed that the two lines likely split approximately 33.5 million years ago before the existence of the ocean currents experienced today.
Like the telescope octopus, many other unique sea creatures inhabit the dark depths of the deep sea. Learn about the importance of the deep sea ecosystem here.
