Saturday, February 21, 2026

Giant sloth and horse fossils found under cenote in Yucatán

Archeologists in Mexico have found fossils of extinct animals in a cenote in Umán, Yucatán, including those of a giant sloth and prehistoric horses.

Speleologist (cave researcher) Cristián Selun said the fossils date back to the ice age, between 7,000 and 10,000 years ago. This discovery sheds light on the prehistoric fauna that inhabited the region.

A white fossilized bone, one of many fossils found in the Yucatán cenote.
Scientists found more than 20 pieces of fossilized bone in the area. (Yucatán Informa/X)

“The first bones that we saw were those of the sloth,” scuba diver Arnaldo Marruco told news outlet NMás. “It was in other nearby areas that we found more bones, including a jaw, which was of a different size.”

According to scientists, the horses are of the Equus conversidens species while the giant sloth belongs to the species Nothrotheriops shastensis. The sloth weighed 300 kilograms and measured three meters long.

The remains were discovered in 2023 in the Dzombakal cenote in the San Antonio Mulix community of Yucatán. However, the results of their identification and analysis were only recently released by a team of scientists led by paleontologist Jerónimo Avilés Olguín in collaboration with the National Institute of Anthropology and History (INAH).

According to Selun, the bones must be identified and compared with others found in Quintana Roo. The on-site verification process takes time, “especially because human bones have also been found here,” he said.

A yellow fossil, which appears to be a jaw bone, next to a ruler.
The findings included vertebrae, jaws, and arm and leg bones. (Yucatán Informa/X)

To date, scientists have found more than 20 pieces of fossilized bone in the area, including vertebrae, jaws, arm and leg bones and other fossil remains. However, this is the first time a giant sloth has been discovered in Yucatán.

“It was a very large animal. We found the long parts of the legs, very large ribs and shoulder blades,” Marruco said. 

These fossil fragments are protected by INAH since extracting them is forbidden. They’re also monitored and cared for by the community’s inhabitants, who have pledged to preserve the prehistoric findings.

With reports from NMás, Debate and López Dóriga

1 COMMENT

Have something to say? Paid Subscribers get all access to make & read comments.
Sheinbaum and two Mexican generals observe a military band on Army Day in Puebla

Mexico’s week in review: Sheinbaum says no to the US — and yes to Canada

0
The third week of February was a busy one for Mexico as it courted Canada, rebuffed Trump, racked up drug busts and caught a Supreme Court break on tariffs. Here are the week's biggest stories.

MND Local: Is San Miguel de Allende about to receive passenger rail service?

0
Is San Miguel de Allende set to get passenger rail service? President Sheinbaum says yes.
sad, unhappy Trump

US Supreme Court strikes down Trump’s tariffs: What does it mean for Mexico?

15
The ruling frees Mexico from paying certain Trump tariffs, such as the "fentanyl tariff" and the "reciprocal tariffs," though other exporting nations will probably get more relief than Mexico.
BETA Version - Powered by Perplexity