How old are axolotls?

[benjamin]

I recently saw an educational film which stated that many lakes often only last some tens of thousands of years, depending on size and temperature. I was wondering: if the axolotl is exclusive to only a few interconnected lakes, then it can't have been around for a very long time. Does anybody know specific information about how old the axolotl is as a species?

 

[joan]

Axolotls could very well have existed in terrestrial 'tiger salamander' form before developing neotenic traits. They also could have migrated from other ponds.