Axolotls have barely visible vestigial teeth, which would have developed during metamorphosis.
Many species within the axolotl's genus are either entirely neotenic or have neotenic populations.
Axolotls should not be confused with waterdogs, the larval stage of the closely related tiger salamanders (Ambystoma tigrinum and Ambystoma mavortium), which is widespread in much of North America which also occasionally become neotenic.
The surviving species of rhinoceros have a thick protective skin, 1.5-5 centimeters thick, formed from layers of collagen positioned in a lattice structure.
The genus has become famous due to the presence of axolotl, widely used in research, and the tiger salamander (Ambystoma tigrinum, Ambystoma mavortium).
Artificial metamorphosis also dramatically shortens the axolotl's lifespan, if they survive the process.
Axolotls commonly are kept as pets in the United States, Great Britain (under the spelling Axlotl), Australia, Japan, and other countries.
Adult axolotls possess features typical of salamander larvae, including external gills and a caudal fin extending from behind the head to the vent.
Unaware of their neoteny, Auguste Dumйril was surprised when, instead of the axolotl, he found in the vivarium a new species, similar to the salamander.
Axolotls are used in heart defect studies due to the presence of a mutant gene that causes heart failure in embryos.
Six adult axolotls (including a leucistic specimen, pale pink with black eyes) were shipped from Mexico City to the "Jardin des Plantes" in Paris in 1863.
Axolotls are members of the Ambystoma tigrinum (Tiger salamander)-complex, along with all other Mexican species of Ambystoma.
Fish can also nibble an axolotl's gill stalks and appendages while it is asleep, leading to infection.
Axolotl (or ajolote) is the common name for the salamander Ambystoma mexicanum, which is the best-known of the Mexican neotenic mole salamanders belonging to the Tiger Salamander complex.
Unfortunately for the axolotl, Lake Chalco no longer exists, as it was drained by humans to avoid periodic flooding, and Lake Xochimilco remains a diminished glimpse of its former self, existing mainly as canals.
The axolotl is carnivorous, consuming small prey such as worms, insects, and small fish in the wild.
During transformation, the air in the vivarium must remain moist, and the maturing axolotl sprayed with a fine mist of pure water.
In captivity, axolotls can be fed a variety of readily available foods, including trout and salmon pellets, frozen or live bloodworms, earthworms, and waxworms on occasion.
A neotenic axolotl will live an average of 10–15 years (though an individual in Paris is credited with achieving 25 years), while a metamorphosed specimen will scarcely live past the age of five.
Axolotls exhibit a property called neoteny, meaning the retention, by adults in a species, of traits previously seen only in juveniles.
Axolotls also enjoy beef liver and sometimes small prawns.
Axolotls locate food by smell, and will "snap" at any potential meal, sucking the food into their stomachs with vacuum force.
The axolotl is, therefore, used as a model for the development of limbs in vertebrates.
Axolotls have four different colors, two commonly occurring colors and two mutants.
A sexually-mature adult axolotl, at age 18–24 months, ranges in length from 15–45 cm (6–18 inches), although a size close to 23 cm (9 inches) is most common and greater than 30 cm (12 inches) is rare.