Unknown 'Hoff' crab species found

Wed, Jan 4, 2012, 00:00

Scientists have discovered a “lost world” of previously unknown species, including a crab dubbed "The Hoff", thriving in a deep sea hotspot near Antarctica.

Researchers operating a robot submersible found a plethora of unidentified creatures including crabs, starfish, barnacles, sea anemones and an octopus.

The communities were living around volcanic vents deep beneath the Southern Ocean, where temperatures can reach 382C. Hydrothermal vents create a unique environment lacking in sunlight but rich in life-sustaining minerals.

Professor Alex Rogers, from Oxford University’s Department of Zoology, who led the research, said: “Hydrothermal vents are home to animals found nowhere else on the planet that get their energy not from the Sun but from breaking down chemicals, such as hydrogen sulphide.

“The first survey of these particular vents, in the Southern Ocean near Antarctica, has revealed a hot, dark, ‘lost world’ in which whole communities of previously unknown marine organisms thrive.” A camera-equipped Remotely Operated Vehicle (ROV) was sent on a series of dives on the East Scotia Ridge to depths of more than 2,000 metres.

Highlights among the images captured included huge colonies of a new species of yeti crab clustered around vent chimneys, and an undescribed predatory seven-armed sea star. Scientists have dubbed the yeti crab "The Hoff" because of its hairy chest. Prof Rogers said the crab would be given a formal scientific name later.

A mysterious pale-coloured octopus, as yet unidentified, was also spotted nearly 2,400 metres deep on the seafloor.

The discoveries were described today in the online journal Public Library of Science Biology.

“What we didn’t find is almost as surprising as what we did,” Prof Rogers added. “Many animals such as tubeworms, vent mussels, vent crabs and vent shrimps, found in hydrothermal vents in the Pacific, Atlantic and Indian Oceans, simply weren’t there.” The cold Southern Ocean may act as a barrier to other species that make their homes around hydrothermal vents, the scientists believe.

The uniqueness of East Scotia Ridge also suggests that vent ecosystems may be much more diverse than was previously thought.

Prof Rogers was on an international panel of experts who warned last June that the world could be facing an unprecedented era of marine extinction.

“These findings are yet more evidence of the precious diversity to be found throughout the world’s oceans,” he said. “Everywhere we look, whether it is in the sunlit coral reefs of tropical waters or these Antarctic vents shrouded in eternal darkness, we find unique ecosystems that we need to understand and protect.”

Last week University of Southampton scientists reported finding another ecological hotspot around “black smoker” vents deep below the Indian Ocean.

Reuters