Axolotl

It is noted for its appearance and its demonstration of neoteny, remaining in its aquatic larval form and not undergoing metamorphosis to an adult stage, even reaching sexual maturity in the larval stage.

A fully grown Axolotl, at age 18-24 months, ranges in length from 150-450 mm, although a size close to 230 mm is most common and greater than 300 mm is rare. They have distinctive 'fern-like' gill structures and also breathe through the skin, the Axolotl also possesses basic lungs. In colour they range from albino or white to black, through greys, tans and browns, wild Axolotls are rarely white. The Axolotl is carnivorous, hunting small prey such as insects and small fish which are swallowed whole.

There is substantial evidence to support the theory that the Axolotl is very closely related to the Tiger salamander (Ambystoma tigrinum), except for the genetic neoteny. An Axolotl can metamorphose and in the adult stage is very similar to Ambystoma mavortium, a subspecies of the Tiger Salamander.

Native only to Lake Xochimilco[?] and Lake Chalco[?] the wild population has been put under heavy pressure by the growth of Mexico City. It is currently listed by CITES as an endangered species. In Spanish it is called the Salamandra ajolote.

The Axolotl is used in research and large numbers are bred in captivity. The feature of the salamander that attracts most attention is its healing, the Axolotl does not heal by scarring and is capable of regenerating entire lost appendages and, in certain cases, more vital structures. Another attractive feature, for research, is the large and robust embryos.

The name is derived from the Aztec nahuatl.