The new “Pandoravirus” species are so named because “opening” them has spawned so many questions about the nature of life.
One was found in a freshwater pond near Melbourne, Australia, and the other off the coast of central Chile.
They are larger than any other viruses ever discovered, and more than 90 percent of their genes are new to science.
The largest is a full 1 micrometer long and can easily be seen through a standard lab microscope.
It was found in sediments at the mouth of the Tunquen River in Chile and has the largest genome of any known virus.
“One of our jokes is that either they are from outer space or from a cellular ancestor that’s now disappeared,” said researcher Chantal Abergel from CNRS, the French national research agency.
Viruses are technically not alive because they can’t generate their own energy.
It’s thought that the Pandoraviruses were once live, self-supporting cells that downsized themselves to viruses by becoming viral parasites.