axolotl

The axolotl, scientific name Ambystoma mexicanum, is a neotenic salamander native to the lake system of Xochimilco near Mexico City. Unlike most salamanders, axolotls retain larval features—such as external gills and an aquatic lifestyle—throughout life. They typically reach about 15 to 30 centimeters in length and have a broad head, lidless eyes, and a dorsal fin that runs along the back.

In the wild, axolotls inhabit cool, slow-moving canals and lakes with vegetation. They are carnivorous, feeding on aquatic invertebrates, crustaceans, insect larvae, small fish, and similar prey. Their reliance on clean, stable water makes them particularly sensitive to environmental changes.

Reproduction occurs in water with external fertilization. Females lay eggs that attach to vegetation; the eggs hatch into aquatic larvae. Most axolotls remain in the larval form (neoteny) for life, but metamorphosis can be induced experimentally by thyroid hormone; naturally it is rare.

Axolotls are renowned for their regenerative abilities. They can restore lost limbs, damaged spinal cord, heart tissue, and parts of the brain, often with little scarring. This remarkable regeneration has made them a key model organism in developmental and regenerative biology. The genome has been sequenced, and many lines are used in research, including transgenic and gene-edited strains.

Conservation status in the wild is critical. Habitat loss, water pollution, and invasive species have reduced wild populations, and axolotls are chiefly maintained in captivity for research, education, and the pet trade. Wild individuals persist mainly in isolated pockets around Mexico City, while captive populations are widespread worldwide.

In captivity, axolotls require cool, clean water, gentle filtration, and routine maintenance. They are carnivorous, eating earthworms, bloodworms, brine shrimp, and small fish. They can live for about 10 to 15 years in well-managed aquariums.