Scientists have identified two species of crocodiles unknown previously off the Yucatán peninsula in Mexico, which can already be at risk of extinction due to small populations and habitat pressures.
The new species have been found on Cozumel Island and Banco Chinchorro, an atoll coral, and are genetically distinct from the American crocodile (Crocodylus acutus), according to a study published in the journal Phylogenetics and molecular evolution.
The discovery carries the total number of crocodile species of the new world known to six.
So far, scientists only recognized American, Morelet, Cuban and Orinoco crocodiles in the region.
Researchers from the University of Canada McGill, as well as Mexico and Panama partners, have carried out genetic and anatomical analyzes which revealed enough variations to classify the populations of Cozumel and Banco Chinchorro as a distinct species.
“These results were completely unexpected,” said the main author José Avila-Cervantes. “We assumed Crocodylus acutus was only one species ranging from Baja California to Venezuela and across the Caribbean. »»
The research concerned the collection of DNA and skull measures from crocodiles in the two places. The notable differences included the shape of the skull, with Banco Chinchorro crocodiles displaying longer and wider walls.
The study estimates that each new species has less than 1,000 reproductive individuals and that the effective size of populations can be as low as 500. Although the current number seems stable, scientists have warned that the limited housing and the increase in development linked to tourism could present serious risks.
“Biodiversity disappears faster than we can discover what we lose,” said McGill’s main author Hans Larsson. “Most crocodile species are already endangered. The protection of these habitats is essential. “
Cozumel, a major cruising destination, received more than 1.5 million visitors in the first three months of 2025 only. Banco Chinchorro, which is part of the Meso-American barrier reef system, is also ecological.
The researchers urged governments and conservation groups to implement more strict land use policies and to establish habitat protections to preserve newly identified species.
Although the reptiles are not yet officially named, the researchers have suggested that the references to their geographic isolation – such as Crocodylus Cozumelus Or chinchorri– Perhaps being used in their taxonomic classification.
The study underlines how natural barriers such as ocean currents in the Yucatán region have helped to shape biodiversity by isolating species and allowing a unique evolution.
“These crocodiles are scalable survivors,” said Larsson. “Now that we know that they exist, we must make sure that they do not disappear before they are even named.”
