Scientists Have Identified a New Fossil Species of Axolotl in Mexico
Overview
Researchers have formally described Ambystoma quetzalcoatli, the first fossil salamander ever identified in Mexico. The discovery confirms that axolotls and their close relatives have inhabited Mexican territory for millions of years, long before the species we know today, Ambystoma mexicanum, became a fixture of the canals of Xochimilco. For paleontologists, the find fills a long-standing gap: despite Mexico's extraordinary living diversity of mole salamanders, its fossil record for the group had remained essentially empty until now.
What Is Ambystoma quetzalcoatli?
Ambystoma quetzalcoatli belongs to the genus Ambystoma, commonly known as mole salamanders, which includes the modern axolotl along with dozens of other species found mostly in North America. The name honors Quetzalcoatl, the feathered-serpent deity of Aztec mythology — a fitting tribute given that axolotls themselves are named after another Aztec god, Xolotl. By linking the fossil to this mythological lineage, researchers underline the deep cultural and biological roots axolotl-like animals have in the region.
Why Fossil Salamanders Are So Rare
Salamander fossils are notoriously difficult to find and identify. Their skeletons are small, thin, and often poorly mineralized, meaning they rarely survive the fossilization process intact. Add to that the acidic, wet environments many salamanders prefer — conditions that tend to destroy bone rather than preserve it — and it becomes clear why global salamander fossil records remain sparse compared to those of larger vertebrates. Mexico, home to one of the richest concentrations of living Ambystoma species anywhere on Earth, had nonetheless produced zero confirmed fossil salamanders prior to this discovery.
Why This Discovery Matters
Beyond closing a gap in the fossil record, Ambystoma quetzalcoatli gives scientists a rare data point for reconstructing how mole salamanders evolved and dispersed across Mexico over deep time. It suggests that the lineage leading to the modern axolotl — a species now critically endangered in the wild due to habitat loss, pollution, and invasive species in the Xochimilco wetlands — has a far older presence in the region than direct fossil evidence had previously shown. That longer evolutionary history adds context to ongoing conservation efforts, framing the modern axolotl not as an isolated curiosity but as the surviving branch of a much older Mexican lineage.
FAQ
Is Ambystoma quetzalcoatli the ancestor of today's axolotl? It is a related fossil species within the same genus, not necessarily a direct ancestor; researchers use it to better understand the broader evolutionary history of the group rather than to draw a straight line to Ambystoma mexicanum.
Why hadn't a fossil salamander been found in Mexico before? The combination of fragile skeletal remains and preservation-unfriendly environments has historically made salamander fossils hard to locate and confirm, even in regions with high living diversity.
Source
Originally published at www.wired.com.