Mexican scientists said Wednesday they have discovered the fossilized remains of a previously unknown species of giant sloth that lived 10,000 years ago and died at the bottom of a sinkhole.

The Pleistocene-era remains were found in 2010, but were so deep inside the water-filled sinkhole that researchers were only gradually able to piece together what they were, the National Institute of Anthropology and History (INAH) said in announcing the find.

Scientists have so far hauled up the skull, jawbone, and a mixed bag of vertebrae, ribs claws and other bones, but the rest of the skeleton remains some 50 meters (165 feet) under water, the INAH said.

The Pleistocene-era remains were found in 2010, but were so deep inside the water-filled sinkhole that researchers were only gradually able to piece together what they were, National Institute of Anthropology and History said in announcing the find. The skull is pictured

Researchers are planning to bring up the rest by next year to continue studying the find—including to estimate how big the animal was.

'They'll be putting the pieces together like a puzzle,' INAH spokesman Arturo Mendez told AFP.

The skeleton is nearly complete, leading scientists to believe the sloth 'fell into the sinkhole when it was dry or had only a little water at the bottom,' the researchers said.

They have named the new species Xibalbaonyx oviceps, and nicknamed it 'Pote.'

Mexican scientists said Wednesday they have discovered the fossilized remains of a previously unknown species of giant sloth that lived 10,000 years ago and died at the bottom of a sinkhole

Scientists have so far hauled up the skull, jawbone, and a mixed bag of vertebrae, ribs claws and other bones, but the rest of the skeleton remains some 50 meters (165 feet) under water, the INAH said

An initial analysis suggests the sloth lived between 10,647 and 10,305 years ago, they said—an era when giant creatures of all kinds roamed the Earth.

Mexico is known for its numerous sinkholes, known here as 'cenotes' and often filled with stunning emerald and turquoise waters illuminated by a shaft of light from above.

The area where the sloth was found, amid the pristine beaches of the Yucatan peninsula, is home to some of the most extensive networks of underwater caves on Earth, a magnet for cave divers from around the world.

Mexico is known for its numerous sinkholes, known here as 'cenotes' and often filled with stunning emerald and turquoise waters illuminated by a shaft of light from above. They suspect the sloth, dubbed 'Pote' fell into a sinkhole and died

THE HARLAN'S GROUND SLOTH The giant mammal roamed the Los Angeles basin 11,000 years ago Fossil was identified as a sloth proximal femur head fragment (Sloth's Hip Joint Bone) The sloths grew up to 10 feet in length and weighed up to 1,500 pounds. The giants were bulky, with short necks, powerful chests, and massive jaws. They had three claws per hand, which they could use for digging, grabbing, or defending themselves. Under their coat of coarse, brown hair, they had small, nickel-sized, bony plates embedded in their skin as protective armor, similar to armadillos today. Ground sloths originated in South America, before the continent was connected to North America by way of Panama. A herbivore that fed on grasses, shrubs, and flowering plants, it used its stout snout and keen nose to sniff for food. It lived in open grassland habitats and fed mostly on grass. Advertisement

Earlier this year, crews digging a tunnel for a new Los Angeles train line have found the remains of an ancient giant sloth.

The Metropolitan Transportation Authority says a fossilized hip joint was discovered on May 16 in a layer of sandy clay 16 feet below a major thoroughfare where the new rail line is being built.

The bone is from a Harlan's ground sloth, a mammal that roamed the Los Angeles basin 11,000 years ago.

The sloths grew up to 10 feet in length and weighed up to 1,500 pounds.

A bone from an extinct bison also was found.

Earlier this year, crews digging a tunnel for a new Los Angeles train line have found the remains of an ancient giant sloth. The image above shows the fossilized hip joint of the ancient ground sloth

Large mammals flourished in the LA area thousands of years ago.

Excavations for train projects have turned up bison and camel bones as well as mastodon teeth and tusk fragments.

Paleo Solutions, the firm that made the find, said 'This is an amazing discovery.

'If this is a Harlan's Ground Sloth (largest and most common of three species of ground sloth found at the Tar Pits) then it could have easily weighed up to 1,500 pounds and measure up to 10 feet in length.'

The two partial large mammal bones were discovered in a sandy clay layer area 16 feet under Crenshaw Bl between 63rd St. and Hyde Park Bl on On May 16th.

The first fossil was determined to be a bison right proximal radius (Bison Bone) and the second fossil is identified as a sloth proximal femur head fragment (Sloth's Hip Joint Bone).

The fossils will be held at the Paleo Solutions laboratory until the Project is complete, at which time it will be transferred to the Natural History Museum of Los Angeles County or other accredited repository for permanent curation.

'Although it is difficult to find out all of our Sloth's history from just one bone, there is some information that can be gathered from our staff's visit to the Tar Pits,' Paleo Solutions said.

'Assuming the sediments are the same age as the Tar Pits, Harlan's Ground Sloth (Paramylodon Harlani) lived in the Los Angeles basin 40,000-11,000 years ago (Late Pleistocene). '

Prior to this, a Paramylodon Harlani fossil was uncovered in Beaumont, CA and it was about 1.3-1.8 million years old (Early Pleistocene).

This type of Sloth lived in North America during the Pliocene through Pleistocene epochs, living from around 4.9 million years ago to 11,000 years ago.