One of the most characteristic and abundant amphibian taxa of South American temperate forests is Eupsophus. The ten currently recognized species of the genus have been divided in two species groups, roseus and vertebralis, but most of them, eight, belong to the roseus group. Recent phylogeographic and phylogenetic studies have suggested that species diversity of the roseus group could be underestimated. An examination of the literature shows that species of the roseus group exhibit high levels of variation in their external characteristics, particularly those used as diagnostic characters, which compromises their taxonomy and hinders their field recognition. High levels of variation were also observed in several new populations of the roseus group discovered in southern Chile (36°-40°S), which could not be identified to the species level by their external characteristics. On the other hand, the literature reveals a scarse karyotype differentiation and a high bioacoustic uniformity among the species of the roseus group. We performed a Bayesian phylogenetic analysis using mitochondrial and nuclear genes to reevaluate the species diversity of the roseus group, including all the nominal species of Eupsophus and new populations. This analysis was complemented with three species delimitation approaches, General Mixed Yule Coalescent, multi-rate Poisson Tree Process and Automatic Barcode Gap Discovery. We favored a conservative delimitation of only four species for the roseus group, a result more consistent with the distribution of pairwise genetic distances, and the available chromosome and bioacoustic evidence. The four recognized lineages, which have nearly completely allopatric distributions, are named after the earliest nominal species that they include, but because high levels of phenotypic variation, they are not diagnosable by consistent differences in external morphology. We discuss the implications of this new proposal for the taxonomy and conservation of the genus, and the possible causes of the difficulty to estimate its species diversity.

No abstract

Background: The Mediterranean zone of central Chile (30°to 38°S) is one of the 25 diversity hotspots in the world. However, there are few phylogeographic studies which identify the factors that have influenced population diversification in the fauna of this area. In this study, we investigated the phylogeographic structure of Rhinella arunco, an anuran endemic to Mediterranean Chile, using 160 individuals from 23 localities representative of its entire distribution (32°to 38°S). Results: The haplotype network revealed four haplogroups, three of which overlap geographically and only one of which has an exclusive geographic distribution. An analysis of molecular variance indicated that neither watershed limits nor the main rivers in the current distribution of this species have been important geographic barriers against the dispersion of individuals. Finally, the Geneland analysis showed three population units, one of which concurs with one of the haplogroups found in the haplotype network. Together, these analyses indicated a low level of phylogeographic structure for this species. On the other hand, the highest levels of intrapopulational genetic variation were concentrated in the central part of the distribution (33°to 34°S), which may indicate an effect of Pleistocene glaciations on the genetic diversity of the populations in the extreme south of its range.

Between mid-May and early June of 1839, members of the United States Exploring Expedition collected diverse anurans in the environs of Valparaíso, Chile, later described by Girard in 1853. Of this set of species, Metaeus timidus, described there as a new genus and species, attracts attention because is a name that practically disappeared from the herpetological literature. Its identification, along with that of the other Chilean taxa collected by the USEE (Cystignathus nebulosus Girard, 1853, Pleurodema bibroni Tschudi, 1838, Pleurodema elegans Bell, 1843, Bufo lugubrosus Girard, 1853, Bufo thaul Lesson, 1826 and Metaeus timidus Girard, 1853) are the main objectives of this contribution.

High Andean environments of central Chile (32°–38°S) are inhabited by several endemic species of the genus Alsodes. Two of them, A.pehuenche and A.hugoi, have geographic distributions restricted to their type locality and surroundings. The Chilean government classifies A.pehuenche as Critically Endangered (like the IUCN) and A.hugoi as Vulnerable. In this study we report 16 new localities of Alsodes, 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 to A.pehuenche and A.hugoi were observed, as well as specimens of Alsodes that 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 to A.pehuenche, while most of those located south of that area would be A.hugoi. The exception is Cajón de Plaza (36°23’S), where specimens with sequences of A.hugoi or A.pehuenche coexist, whose taxonomic status could not be determined. These findings imply not only a westward range extension of A.pehuenche in Chile of about 14.5 km and of A.hugoi about 100 km southward, but also that practically all the first order streams of the Andes of central Chile would be inhabited by populations of Alsodes. 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.