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Darwin's frogs (Rhinoderma darwinii and R. rufum) are two species of mouth-brooding frogs from Chile and Argentina. Here, we present evidence on the extent of declines, current distribution and conservation status of Rhinoderma spp.; including information on abundance, habitat and threats to extant Darwin's frog populations. All known archived Rhinoderma specimens were examined in museums in North America, Europe and South America. Extensive surveys were carried out throughout the historical ranges of R. rufum and R. darwinii from 2008 to 2012. Literature review and location data of 2,244 archived specimens were used to develop historical distribution maps for Rhinoderma spp. Based on records of sightings, optimal linear estimation was used to estimate whether R. rufum can be considered extinct. No extant R. rufum was found and our modelling inferred that this species became extinct in 1982 (95% CI, 1980-2000). Rhinoderma darwinii was found in 36 sites. All populations were within native forest and abundance was highest in Chiloé Island, when compared with Coast, Andes and South populations. Estimated population size and density (five populations) averaged 33.2 frogs/population (range, 10.2-56.3) and 14.9 frogs/100 m(2) (range, 5.3-74.1), respectively. Our results provide further evidence that R. rufum is extinct and indicate that R. darwinii has declined to a much greater degree than previously recognised. Although this species can still be found across a large part of its historical range, remaining populations are small and severely fragmented. Conservation efforts for R. darwinii should be stepped up and the species re-classified as Endangered.

The southern part of the Altiplano of the Andes Range is characterized by a complex hydrography, due to an intense geologic activity and the effects of the Pleistocene glaciations. This has produced a high degree of diversity at the species level in some aquatic taxa (e.g., fish and amphibians), which suggests that these same processes have produced divergence at the intraspecific level in co-distributed taxa. We investigated the genetic variation in populations of the anuran Rhinella spinulosa which represent its entire distribution in the extreme north of Chile (17°44′S-23°47′S). Haplotype networks of the mitochondrial control region recognized two main lineages, one of which is distributed from the northern boundary of Chile to the Salar de Alconcha and the other from the Salar de Carcote to the locality of Tilomonte. The northern lineage showed little phylogeographic structure; a few very frequent haplotypes are widely distributed. The southern lineage had greater structure, due principally to the high divergence of the populations from the eastern springs of the Salar de Atacama. Fu's Fs test and the mismatch distributions suggested that most of the populations of both lineages are in the process of demographic expansion. The spatial distribution of the genetic variability was correlated with the hydrography and the paleoclimatological data available for the region, which suggested that geographic expansions followed by periods of contraction of population ranges, together with sporadic floods may explain the observed phylogeographic patterns. [ABSTRACT FROM AUTHOR]