Researchers have excavated a remarkable trove of ancient treasures in a Los Angeles subway shaft that held mollusks, sand dollars and part of a sea lion's mouth that may be 2 million years old.

Discovered in an exploratory subway shaft for the Westside expansion, the fossil dig is close to the La Brea Tar Pits, the famous Ice Age fossil excavation site, the Los Angeles Times reported.

"Here on the Miracle Mile is where the best record of life from the last great ice age in the world is found," paleontologist Kim Scott, field and laboratory director with Cogstone Resource Management, told the L.A. Times.

She compared the subway shaft, which also held Monterey cypress cones, to "walking along an ice age shoreline."

Working with the Los Angeles County Metropolitan Transportation Authority, researchers from Cogstone Research Management and the George C. Page Museum are exploring the shaft and cataloguing the discoveries.

The fossil finds are being collected in plastic takeout containers that won't disturb the asphalt surrounding the specimens.

"Here in Mid-Wilshire," MTA spokesman Dave Sotero told the L.A. Times, "L.A.'s prehistoric past is meeting its subway future."

About 18 feet wide by 38 feet long, the exploratory shaft is thought to reveal a slice of life from the Pleistocene age, which scientists mark at 100,000 to 330,000 years ago. The Pleistocene climate is said to be cooler and wetter, and the Pacific Ocean occupied more space.

So far, the area has held geoducks, clams, snails, mussels and tusk shells as well as wolves, saber-toothed cats and ground sloths, according to the L.A. Times.

"Even though we're finding fossils older than what's found at La Brea, none of the identified fossils found to date are extinct," Scott told the L.A. Times. "We can still find all the plants and animals in California."

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