Ambystoma

Ambystoma is a genus of mole salamanders in the family Ambystomatidae, native to North America. The genus includes large, stout-bodied salamanders that inhabit forests, wetlands, grasslands, and seasonally flooded areas from southern Canada to Mexico. Adults are largely terrestrial and subterranean, often found under logs or leaf litter, with coloration ranging from dull browns and greens to striking patterns such as yellow or orange blotches seen in some species.

Most Ambystoma species breed in spring in ponds or slow-moving streams. Eggs are laid in water, and the aquatic larvae have external gills and finned tails. In many populations, larvae metamorphose into terrestrial juveniles or adults. Some lineages exhibit neoteny, remaining aquatic and sexually mature as adults; the axolotl (Ambystoma mexicanum) is the best known neotenic species and is endemic to the Valley of Mexico. Other populations also display facultative neoteny in response to environmental conditions.

Ecology and behavior: Ambystoma are opportunistic predators, feeding on insects, worms, crustaceans, and small amphibians. They are largely nocturnal or crepuscular and spend much time underground, emerging to breed during rains. They depend on wetlands, and loss or degradation of these habitats threatens many species.

Conservation and significance: The genus comprises about 30–40 described species, many with restricted ranges and declining populations due to habitat loss, pollution, and disease. The axolotl is among the best-studied amphibians in biomedical research due to its regenerative abilities, and it remains a classic vertebrate model. Some Ambystoma species are kept in captivity for education and the pet trade.