August 21, 2009

New Worm Species Discovered – ‘Green Bomber’

Researchers have discovered a new species of worm, dubbed the "green bomber."

The worms, which live thousands of feet beneath the sea, can cast off green glowing body parts.

In all, a total of seven new worm species were discovered by a research team led by Karen Osborn of the Scripps Institution of Oceanography at the University of California.

The report on the worms will be in Friday's edition of the journal Science.

"We found a whole new group of fairly large, extraordinary animals that we never knew anything about before," Osborn said.

"These are not rare animals. Often when we see them they number in the hundreds. What's unique is that their habitat is really hard to sample."

The worms, which range in size from three-fourths of an inch to four inches, live at depths between 5,900 feet to 12,000 feet.  They are largely transparent, except for their gut.

The creatures propel themselves with long bristles that act like swimming paddles.

"They have a very strange way of using bioluminescence," Osborn explained.

When disturbed, the worms release appendages, like bombs, that glow bright green.

"They drop one or two at a time and if you keep harassing them they will keep dropping them," she said, adding that the worms are capable of regenerating the appendages.

According to Osborn, this is the first time this has been seen in swimming worms.

"We're not sure who their predators are," added Osborn.

The green bombers are fascinating from an evolutionary standpoint, says Greg Rouse, coauthor of the study.

Rouse believes the ancestors of the green bombers live on the seafloor, and that their bombs were gills at one point.

"The relatives have gills that appear to be in exactly the same places as the bombs," said Rouse.

"The gills can fall off very easily so there's a similarity of being detachable, but for some reason the gills have transformed to become these glowing little detachable spheres."

The new species has been given the scientific name Swima bombiviridis.

According to researchers, the discovery is another example of how little scientists know about life in the deep oceans.

"With fairly limited time on submersible vehicles, mainly off California, we've picked up seven new species. It goes to show that we have much more exploration ahead and who knows what else we'll discover?" said Rouse.


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