Axolotls are very odd animals. They're amphibians, related to frogs, toads, and newts. They have a frill of gills behind their head that they use to breathe, since they live in the water all the time.
The one I've drawn is an albino, but they come in various colors just as salamanders and newts do. The Aztecs used to eat them (much as we eat frog's legs today!)
They have no eyelids. They're carnivorous- they like to eat anything alive that will fit in their mouth and that they can find. They're also very resilient; if they lose a leg, they can simply grow a new one.