Researchers from the Antarctic Geological Drilling (ANDRILL) Program have described a new species of anemone from waters beneath the Ross Ice Shelf, Antarctica.
In an underwater image, Edwardsiella andrillae anemones protrude from the bottom surface of the Ross Ice Shelf. They glow in the camera’s light. Image credit: Frank Rack / ANDRILL Science Management Office, University of Nebraska-Lincoln.
The newly discovered species, named Edwardsiella andrillae, is the first known to live in ice.
These anemones are very small, measuring less than 2.5 cm (1 inch) in length. They live upside down, hanging from the ice, compared to other sea anemones that live on or in the seafloor.
“The discovery was total serendipity. When we looked up at the bottom of the ice shelf, there they were,” said Dr Frank Rack, executive director of the ANDRILL Science Management Office at the University of Nebraska-Lincoln and a co-author of the paper published in the open-access journal PLoS ONE.
Edwardsiella andrillae. Image credit: Frank Rack / ANDRILL Science Management Office, University of Nebraska-Lincoln.
Researchers had lowered a camera-equipped robot into a hole bored through the 270-m-thick shelf of ice that extends more than 600 miles northward into the Ross Sea from the grounding zone of the West Antarctic Ice Sheet. Their mission was to learn more about the ocean currents beneath the ice shelf. They didn’t expect to discover any organisms living in the ice, and surely not an entirely new species.
“The anemones measured less than an inch long in their contracted state – though they get three to four times longer in their relaxed state,” said study lead author Dr Marymegan Daly of Ohio State University.
“Each features 20 to 24 tentacles, an inner ring of eight longer tentacles and an outer ring of 12 to 16 tentacles.”
After using hot water to stun the creatures, the scientists used an improvised suction device to retrieve them from their burrows. Anemones were then transported to McMurdo Station for preservation and further study.
Because the scientists were not hunting for biological specimens, they were not equipped with the proper supplies to preserve them for DNA/RNA analyses. The anemones were placed in ethanol at the drilling site and some were later preserved in formalin at McMurdo Station.
Known localities of Edwardsiella andrillae. Image credit: Daly M et al.
“Many mysteries remain. Though some sea anemones burrow into sand with tentacles or by expanding and deflating the base of their bodies, those strategies don’t seem feasible for ice. It is also unclear how they survive without freezing and how they reproduce. There is no evidence of what they eat, although they likely feed on plankton in the water flowing beneath the ice shelf,” Dr Daly said.
The scientists hope to return to Antarctica as early as 2015 to continue studying Edwardsiella andrillae and other organisms beneath the ice shelf.
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Daly M et al. 2013. Edwardsiella andrillae, a New Species of Sea Anemone from Antarctic Ice. PLoS ONE 8 (12): e83476; doi: 10.1371/journal.pone.0083476
