Ambystoma quetzalcoatli sp. nov., a new species of fossil axolotl (Caudata: Ambystomatidae) from the Pliocene of Santa María Amajac, Hidalgo, Mexico

Axolotls are a modern group of salamanders in which some species retain their juvenile characteristics into adulthood (neoteny), and some species have the amazing capacity of self-healing. A recent paleobiological study described a new fossil species of axolotl that was named Ambystoma quetzalcoatli in honor of the Mesoamerican deity Quetzalcoatl. A. quetzalcoatli was described on the basis of some of the first known articulated skeletons for the genus Ambystoma, discovered in the early 2000s near the locality of Santa María Amajac in the State of Hidalgo, Mexico. A. quetzalcoatli was a neotenic species that had a unique skull morphology that differentiates it from the extant species of axolotls, and it inhabited a highly diverse lacustrine ecosystem during the Pliocene, about four million years ago. Additionally, A. quetzalcoatli is the oldest known record of the genus Ambystoma for Mexico and the first fossil species of salamander from the country.