The axolotl always has a smile on their face. A salamander related species, the Axolotl is a critically endangered species found in lakes around Mexico City. Their recent popularity in the game Minecraft has made their appearance as endangered almost none existent.
The Axolotl lives in stagnant freshwaters and the gills that hang off their face are actually used for breathing! One of the coolest things about this species is its ability to regrow limbs. Just like a starfish an Axolotl can lose a limb or part of its tail and regenerate a new one. Unlike other salamanders, however, the Axolotl does not go through a complete morphinism to survive out of water. Instead, these creatures do a morphism to maintain a marine life cycle.