Scientists discover an Australian seagrass clone as world's largest plant

Scientists have discovered what seems to be the world's largest plant and it has been living right under our noses in Western Australia.

Left to its own devices and relatively undisturbed by human hands, a single seed – spawned from two different seagrass species ( about 4500 years ago) has grown into what is now believed to be the biggest plant anywhere on Earth.

Found itself nestled in a favorable spot somewhere in what is now known as Shark Bay, just off Australia's west coast, the plant is about 200 sq km (77 sq miles, or about 20,000 rugby fields, or just over three times the size of Manhattan island), as per The Guardian's report.

The project began as scientists from the University of Western Australia and Flinders University set out to study the genetic diversity of seagrass meadows in the Shark Bay area. The team took samples of shoots from all across the region, in several different environments, then examined 18,000 genetic markers to create profiles of the plants.

Genetic testing then revealed that what was once thought to be part of a giant seagrass meadow in the shallow waters of Shark Bay, near Carnarvon, was actually a single massive clone of Posidonia australis seagrass.

According to the researchers, who published their findings in Proceedings of the Royal Society B today, that makes it the single largest plant known to exist on Earth.

"Certainly by land area, to the best of our knowledge, it is [the largest plant in the world]," said evolutionary biologist and study co-author Elizabeth Sinclair from the University of Western Australia.

"We thought 'what the hell is going on here?'" said Dr Martin Breed, an ecologist at Flinders University. "We were completely stumped."

The one plant now spreads out like a meadow, providing habitat for a huge array of marine species including turtles, dolphins, dugongs, crabs, and fish.

Dr Elizabeth Sinclair, a co-author of the research at UWA, said they hadn't given the plant a nickname, and original samples – pulled from the seagrass meadow – originally had 116 different labels with GPS coordinates when they were stored in a deep freeze ready for genetic sampling.

The plant has formed huge, dense meadows that in some areas stretch as far as the eye can see in all directions. The ribbons of the plant are only 10cm long in some places, but up to a meter in others.