Lake Alchichica, a high-altitude crater lake in eastern-central Mexico, is the only known habitat of the entirely aquatic Taylor’s salamander. The 15-20cm long amphibian exhibits two unusual characteristics not observed in other salamanders. First, it does not undergo complete metamorphosis but rather retains its juvenile characteristics – such as external gills – well into reproductive maturity. The species has also adapted to survive in saltwater – it lives in water that contains the maximum amount of salinity tolerated by most adult amphibians, much higher than most eggs or embryos of amphibians can tolerate.

However, as water from Lake Alchichica is drained for irrigation and human consumption – the water level has dropped several metres in just two decades – salinity continues to increase, posing a threat to the once abundant Taylor’s salamander. This species is now very rarely observed and is threatened with extinction. Lake Alchichica is not protected and because A. taylori does not occur anywhere else in the world, maintaining its habitat is crucial to its survival.