Exciting new research by McGill University scientists, in partnership with Mexican researchers, has led to the discovery of two previously unknown crocodile species. These newly identified species are found on the island of Cozumel and the Banco Chinchorro atoll, located off the coast of the Yucatán Peninsula.
The groundbreaking findings, published in the journal Molecular Phylogenetics and Evolution, challenge long-standing assumptions about the well-known American crocodile (Crocodylus acutus), and underline the urgent need for enhanced crocodile conservation efforts.
Major Discovery in Crocodile Biodiversity
“Biodiversity is disappearing faster than we can discover what we’re losing,” said Professor Hans Larsson, lead investigator from McGill University’s Department of Biology. He emphasized that most crocodile species are already classified as endangered, with rapid coastal development posing a major threat to their survival.
The study aimed to uncover the hidden diversity of crocodiles inhabiting isolated island ecosystems. By analyzing genetic sequences from crocodile populations in Cozumel and Banco Chinchorro, and comparing them with those from across the Caribbean, Central America, and Mexico’s Pacific coast, the researchers uncovered significant genetic differences.
Two New Crocodile Species Identified
The results revealed that the crocodiles in these regions are not just variants of Crocodylus acutus, but represent entirely new species. However, the two newly discovered species have not yet been officially named.
“These findings were completely unexpected,” said José Avila-Cervantes, former graduate student under Professor Larsson and lead author of the study. “Until now, we believed that Crocodylus acutus was a single species distributed from Baja California to Venezuela and throughout the Caribbean. Our research is the first comprehensive examination of both genomic and anatomical variation among these crocodiles.”
Urgent Need for Conservation
The discovery of these new species has critical conservation implications. Each population consists of fewer than 1,000 breeding individuals, making them highly vulnerable to environmental changes and human activities.
“Understanding true species diversity is essential for effective conservation,” Larsson stressed. “Recognizing these populations as distinct species means we must prioritize the protection of their limited habitats. Controlling land development and implementing strategic conservation actions on Cozumel and Banco Chinchorro will be vital for their survival.”
Study Reference
- Title: Novel island species elucidate a species complex of Neotropical crocodiles
- Authors: Jose Avila-Cervantes et al.
- Journal: Molecular Phylogenetics and Evolution (2025)
- DOI: 10.1016/j.ympev.2025.108341