Urban Aquatic Habitats and Conservation of Highly Endangered Species: The Case ofAmbystoma mexicanum(Caudata, Ambystomatidae)

Species with highly restricted distributions are vulnerable to extinction, and modification of natural habitats within their small ranges is a primary threat to their persistence. Expansion of urban development significantly impacts natural habitats and, therefore, threatens local diversity. The Mexican axolotl, Ambystoma mexicanum, is a strictly aquatic species that persists currently in two highly threatened and isolated populations. The current habitat remaining for these species are remnants of a historically extensive lacustrine system that occupied the entire Valley of Mexico, but has been destroyed by the growth of Mexico City. Unexpectedly, a third viable population of axolotls has been found in Chapultepec Park, a public recreational area in the heart of Mexico City. Phylogenetic and haplotype network analyses of mitochondrial DNA sequences confirmed low genetic differentiation and a recurrent lack of monophyly in many of the taxa belonging to the Ambystoma tigrinum species group, including A. me...