axolotl

The rare axolotl Ambystoma mexicanum lives in mountain lakes in Mexico. The capture of specimens as pets and the introduction of predatory fish has led to a decline in numbers.

Aquatic larval form (‘tadpole’) of the Mexican salamander Ambystoma mexicanum, belonging to the family Ambystomatidae. Axolotls may be up to 30 cm/12 in long. They are remarkable because they can breed without changing to the adult form, and will metamorphose into adults only in response to the drying-up of their ponds. The adults then migrate to another pond.

Axolotls resemble a newt in shape, having a powerful tail, two pairs of weak limbs, and three pairs of simple external gills. They lay eggs like a frog's in strings attached to water plants by a viscous substance, and the young, hatched in two to three weeks, resemble the parents. See also neoteny.