Russian scientists have discovered a new, mysterious life form in an ancient lake in Antarctica called Lake Vostok. The bacterial creature is not known to exist anywhere else on Earth.

The team conducted its study by examining samples obtained from the subglacial lake. Lake Vostok is believed to have been isolated from the surface for millions of years. Accordingly, it was not completely unexpected that such an isolated water mass might harbor new microbial life forms.

"After putting aside all possible elements of contamination, DNA was found that did not coincide with any of the well-known types in the global database," Sergei Bulat of the genetics laboratory at the St. Petersburg Institute of Nuclear Physics, said. "We are calling this life form unclassified and unidentified."

Lake Vostok has an area of about 9,320 square miles and reaches a depth of more than 2,624 feet. It is located in the middle of the East Antarctic Ice Sheet, one of the least hospitable environments on Earth. The lowest temperature ever recorded there was minus 89 degrees Celsius.

Despite the harsh conditions, however, the Russians decided to construct Vostok Station there in 1956. Their surroundings soon indicated that there was likely a lake beneath the surface. In the 1990s, British scientists discovered the lake using radar.

Matches between the DNA of the new bacteria and other known organisms never exceeded 86 percent. Any match under 90 percent indicates a new species.

"If it were found on Mars, people would call it Martian DNA," Bulat says. "But this is DNA from Earth."

More testing is needed for conclusive results but it is unlikely to conflict with the initial findings.

The Russians are not the only ones studying Antarctic lakes. The U.S. recently discovered microbial life in Whilans, though Whilans is not known to have been as isolated as Lake Vostok. A British attempt to reach Lake Ellsworth was called off toward the end of last year.