Axolotl

Looks how to spot one

Aquatic salamander that keeps its larval form for life

A smooth-skinned, long-bodied salamander with a wide flat head, small lidless-looking eyes and a permanent 'smile'. Three pairs of feathery external gills fan out behind the head, and a fin runs along the back and tail. The front feet have four fingers and the hind feet five toes. Most adults measure around 23-25 cm, with anything over 30 cm uncommon. Males have a more swollen cloaca, while females look rounder.1234

Personality what they are like

A relaxed, mostly sedentary animal that spends much of its time resting on the bottom of the tank. It becomes lively at feeding time, sniffing out food and snapping it up with a quick suction gulp. Axolotls are solitary by nature and are best enjoyed as display animals rather than pets to hold.12

Daily activity how busy a day looks

Low. Axolotls are slow, bottom-dwelling swimmers that may be active by day or night. They appreciate calm water with little current and some hides, rather than space to roam.216

Grooming and care the hands-on bits

Care is all about water quality: cool, clean, well-filtered water with gentle flow. Keep the temperature around 16-18 °C and never above 24 °C, with pH between 6.5 and 8.0 (about 7.4-7.6 is ideal) and slightly hard water. Lighting should be dim. Choose a bottom that cannot be swallowed, such as a bare floor or large stones, rather than gravel or sand.614

Home where they are happiest

A cool freshwater aquarium of roughly 150 litres for one adult, with low lighting, gentle filtration that keeps the current soft, smooth decor and places to hide.164

Food basics what goes in the bowl

Carnivore. In the wild it eats snails, worms, aquatic insects, small crustaceans and small fish. In captivity it does well on earthworms, bloodworms, blackworms, brine shrimp and sinking salmon or trout pellets. Feed young axolotls daily and adults every two to three days.142

Company who they like around

Naturally solitary and content living alone. Adults of similar size can share a large tank, but very young axolotls and those of quite different sizes should be kept apart because they may nip one another. Keeping the sexes apart prevents unplanned breeding.26

The story where it all began

The axolotl evolved in the lake system of the Valley of Mexico and was well known to the Aztecs, who ate it and named it after Xolotl, their god of fire, lightning and the dead. The Nahuatl name is usually translated as something like 'water dog' or 'water servant'. In 1863 a group of 34 adults was shipped from Mexico City to the Jardin des Plantes in Paris, where zoologist Auguste Duméril was amazed to see a few of them transform into land-dwelling salamanders, which kick-started scientific interest in why axolotls normally never metamorphose. Descendants of these early imports spread through laboratories worldwide, and the axolotl became the most widely used salamander in biological research, especially for studying regeneration. Laboratory and hobby lines produced the many colour forms seen in the pet trade today. Meanwhile the draining of the Valley of Mexico's lakes, which began centuries ago, left the wild population confined mainly to the canals of Xochimilco, and the animal has become a national symbol of Mexico.135

Recognised by the official bits

IUCN Red List

Critically Endangered (wild population)3

CITES

Listed on Appendix II3

Ambystoma Genetic Stock Center, University of Kentucky

NIH-funded centre that maintains and supplies wild-type, mutant and transgenic axolotl lines for research and education5