The iconic axolotl — a salamander-like creature capable of extraordinary regenerative abilities — has disappeared from its only known natural habitat in Mexico's few remaining lakes.
These aquatic creatures are basically salamanders that never grew up. Also known as 'water monsters,' they're a neotenal species whose adult members never lose their gills, allowing them to remain perpetually underwater. They're also unique in that they can regenerate their limbs, including less vital parts of their brains. It's for this reason that they're studied extensively by scientists, which is why many of them are bred and live in labs throughout the world.