do mexican salamanders never need any water to survive during their entire lifetime

Mexican salamanders, like all amphibians, have a complex relationship with water. They may not need to be submerged in water at all times during their life cycle, but it is essential to certain stages of their development and overall well-being.

1. Larval Stage: Mexican salamanders (like Ambystoma mexicanum, the axolotl) begin their lives as aquatic larvae. At this stage, they require water for survival and spend the majority of their time in it.

2. Adult Stage: As they mature, some salamanders lose their gills and develop lungs, allowing them to live on land. However, they still need access to moist environments to keep their skin from drying out.

3. Breeding: Salamanders typically return to water to breed and lay their eggs. They need to be in or near water to reproduce successfully.

4. Habitat: Adult Mexican salamanders can live in semi-aquatic habitats such as marshes, ponds, or damp areas near water bodies.

5. Dietary Needs: Some amphibians are obligate drinkers, needing to drink water to meet their hydration needs. Others can obtain sufficient water from their food or environment.

6. Respiration: While salamanders can absorb oxygen and waste gases through their moist skin, they also need a certain level of humidity to maintain proper skin function.

In summary, Mexican salamanders do not spend their entire lives submerged in water, but they still rely on water or moist environments for various aspects of their life, including reproduction, development, hydration, and skin respiration. A complete absence of water would likely be detrimental to their survival.