High Andean environments of central Chile (32°–38°S) are inhabited by several endemic species of the genusAlsodes. Two of them,A.pehuencheandA.hugoi, have geographic distributions restricted to their type locality and surroundings. The Chilean government classifiesA.pehuencheas Critically Endangered (like the IUCN) andA.hugoias Vulnerable. In this study we report 16 new localities ofAlsodes, corresponding to first order streams, located in the Andes of Chile between 35°58’ and 36°32’S (1800–2470 m). In some of these sites, adults and juveniles morphologically similar toA.pehuencheandA.hugoiwere observed, as well as specimens ofAlsodesthat could not be identified by their external morphology. A Bayesian phylogenetic analysis with mitochondrial sequences (cytochrome b) was performed to identify the new populations to species level. All populations around 36°S belong toA.pehuenche, while most of those located south of that area would beA.hugoi. The exception is Cajón de Plaza (36°23’S), where specimens with sequences ofA.hugoiorA.pehuenchecoexist, whose taxonomic status could not be determined. These findings imply not only a westward range extension ofA.pehuenchein Chile of about 14.5 km and ofA.hugoiabout 100 km southward, but also that practically all the first order streams of the Andes of central Chile would be inhabited by populations ofAlsodes. Both results demonstrate the scarce biogeographic knowledge of the genus in the Andes, which has important implications for its conservation at local and species levels.