British scientists have discovered an astonishing range of creatures living in one of the most inhospitable regions of the deep sea.

Researchers have been exploring and taking samples from the "Dragon Vent" in the south-west Indian Ocean when they found yeti crabs, sea cucumbers and snails living around the volcanic underwater vents. According to Dr. Jon Copley, a marine biologist at the University of Southampton who led the expedition said the animals are unique to the region and hasn't been seen in neighboring parts of the ocean.

"We found a new type of yeti crab. Yeti crabs are known at vents in the Eastern Pacific and there are two species described so far, but they have very long, hairy arms - ours have short arms and their undersides are covered in bristles. They're quite different to the ones that are known from the Pacific," said Copley. "This is the first time a Yeti crab has been seen in the Indian Ocean."

The team also found sea cucumbers, vent shrimps and scaly-foot snails. Sea cucumbers have been previously found at deep sea vents in the Eastern Pacific. This is the first time they've been seen at vents in the Indian Ocean.

Deep-sea vents are fissures in the ocean floor that spew out hot, mineral-rich water. Despite the high temperatures, many species thrive at hydrothermal vents. The Southampton team were interested in the vents on the South West Indian Ridge because they link back to the Mid Atlantic Ridge and the Central Indian Ridge where deep sea life has been recorded. This part of the volcanic ridge is also unusual because it's less volcanically active so hydrothermal vents are fewer and more scattered.

The expedition set off from Cape Town on November 7 and returned to South Africa on December 21. The team explored the Dragon Vent for three days and took hundreds of samples of 17 different creatures. The specimens are now being examined through morphological and genetic testing to determine if they are new species.

Exploring the hydrothermal vents are important because they offer a variety of species that have never been seen before.

"Just like the 19th century naturalists used to go to the Galápagos and other islands to find species there that are different to elsewhere and then use that to understand patterns of dispersal of dispersal and evolution, we can use deep-sea vents to do the same things beneath the waves," Copley said.

"And we need to do that because the exploitation of the deep ocean is overtaking its exploration. We're fishing in deeper and deeper waters, oil and gas is moving into deeper waters and now there's mining starting to take place in deep waters. We need to understand how species disperse and evolve in the deep oceans if we're going to make responsible decisions about managing their resources."

South Africa