22 Ancient Marine Fossils Found in Yucatán Cenotes

Yucatán, Mexico — A team of scientists led by the Institute of Geology at the National Autonomous University of Mexico (UNAM) has uncovered 22 fossil specimens of prehistoric marine animals, including sharks, stingrays, and bony fish, in cenotes across the Yucatán Peninsula. The discovery sheds light on the diversity of vertebrates that inhabited the region millions of years ago when it was a shallow sea.

A Glimpse into Ancient Marine Life

The exploration was conducted in the cenotes Sambulá (Motul), San Juan (Homún), and X-Nabuy (Suma) with the assistance of specialized divers and collaboration from the Autonomous University of Baja California Sur (UABCS) and the Chicxulub Institute.

Analysis of the fossils confirmed the presence of species still found along Mexican coasts today, such as the great white shark (Carcharodon carcharias), bull shark (C. leucas), and copper shark (C. brachyurus), as well as extinct species, including the megalodon (Otodus megalodon) and the tiger shark (Galeocerdo mayumbensis).

One of the most significant findings was the identification of a new species of burrfish, named Chilomycterus dzonotensis, a nod to its cenote habitat. This fossil provides evidence of a reef marine environment during the Miocene and Pliocene epochs in what is now the Yucatán Peninsula.

A Window into the Past

The fossils were found in the Carrillo Puerto Formation, composed of rocks dating back 11 to 3 million years. Researchers suggest this area may have served as a marine refuge for juvenile or small species, offering insights into past local and global extinctions.

“Studying fossils is reconstructing the history of life. What is now a cenote was once a sea. And what is now biodiversity also has a fossil memory,” emphasized Kleyton Cantalice, a paleontologist involved in the project.

The discovery underscores the region’s rich paleontological significance and contributes to a deeper understanding of Mexico’s prehistoric marine ecosystems.