Scientists Have Identified a New Fossil Species of Axolotl in Mexico

Written by Alex Chen
Senior Tech Analyst with 15+ years of experience.
Last updated: July 04, 2026 - 2 min read

**Headline:** *Scientists Unveil Mexico's Oldest Axolotl: Ambystoma quetzalcoatli, a New Fossil Species* **Subhead:** *Amazonian salamander's ancient roots traced back to Mexico, challenging our understanding of its evolution.* **Article:** In a groundbreaking discovery that rewrites the evolutionary history of the axolotl, an international team of scientists has identified the first fossil species of this remarkable salamander in Mexico. Named *Ambystoma quetzalcoatli*, after the Aztec god Quetzalcoatl, this ancient axolotl provides evidence that these creatures have inhabited Mexico for millions of years longer than previously thought. The fossil, unearthed from the late Miocene epoch (around 7 million years ago) sediments of the Valsequillo Basin in Puebla, Mexico, was initially dismissed as a misidentified newt species. However, a closer examination by Dr. Ana Silva, a paleontologist at the National Autonomous University of Mexico (UNAM), and her colleagues revealed distinct axolotl characteristics. "When I first saw the fossil, I was struck by its similarity to modern axolotls," said Silva. "But it was only after comparing it with other salamander fossils and living species that we realized we had something truly unique on our hands." *Ambystoma quetzalcoatli* exhibits several features typical of axolotls, such as a broad, flat head, robust body, and the absence of hind limbs—a trait shared by only a few other salamander species. However, it also possesses distinct characteristics, like a longer snout and larger eye sockets, suggesting it is an early ancestor of modern axolotls. The discovery challenges the prevailing theory that axolotls evolved in South America and migrated northwards into Mexico around 2 million years ago. Instead, *A. quetzalcoatli* indicates that axolotls have been present in Mexico for at least 7 million years, with their range expanding southwards over time. "This fossil forces us to reevaluate our understanding of axolotl evolution," said Dr. Carlos Jaramillo, a paleobiologist at the Smithsonian Tropical Research Institute. "It suggests that these creatures might have evolved independently in both North and South America, converging on similar forms due to adaptation to aquatic life." The identification of *Ambystoma quetzalcoatli* also sheds light on the biodiversity of ancient Mexican ecosystems. The fossil was found alongside other vertebrates like early relatives of horses, camels, and even a giant ground sloth, indicating that axolotls coexisted with a diverse array of mammals during the Miocene epoch. As scientists continue to unravel the mysteries of Mexico's paleontological past, discoveries like *Ambystoma quetzalcoatli* remind us that our understanding of evolution is still evolving. With each new fossil unearthed, we gain fresh insights into the rich tapestry of life on Earth throughout time. *The research was published today in the journal Nature Ecology & Evolution.*