|The bone is believed to be from a Harlan's ground sloth. Pic: LA Brea Tar Pits|
The large hip joint is believed to be from a Harlan's Ground Sloth, that would have lived between 40,000 and 11,000 years ago.
The ancient mammal's bone was found 16ft below Crenshaw Boulevard - a major LA thoroughfare.
The animal would have been up to 10ft long and weighed around 1,500lbs (680kg) - the same as a cow.
|A sample sloth bone (R) next to the giant sloth find. Pic: LA Brea Tar Pits|
A fragment of ancient bison bone was also discovered in the same sandy clay layer.
Now a hub for the world's entertainment industry, the LA lowland would have been full of sloths, bison, ancient camels, mastodons and mammoths during the late Pleistocene era.
|The bison bone (R) next to a sample bison bone. Pic: LA Brea Tar Pits|
Earlier this year LA workmen found bones belonging to an ancient camel and a mastodon and mammoth during a dig to extend another train line beneath Wilshire Boulevard, around 15 miles away.
The fossils will later be transferred, possibly to LA's Natural History Museum, for permanent curation.