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The diversification processes underlying why Amazonia hosts the most species-rich vertebrate fauna on earth remain poorly understood. We studied the spatio-temporal diversification of a tree frog clade distributed throughout Amazonia (Anura: Hylidae: Osteocephalus, Tepuihyla, and Dryaderces) and tested the hypothesis that Miocene mega wetlands located in western and central Amazonia impacted connectivity among major biogeographic areas during extensive periods. We assessed the group’s diversity through DNA-based (16S rRNA) species delimitation to identify Operational Taxonomic Units (OTUs) from 557 individuals. We then selected one terminal for each OTU (n = 50) and assembled a mitogenomic matrix (~14,100 bp; complete for 17 terminals) to reconstruct a Bayesian, time-calibrated phylogeny encompassing nearly all described species. Ancestral area reconstruction indicates that each genus was restricted to one of the major Amazonian biogeographic areas (western Amazonia, Guiana Shield and Brazilian Shield, respectively) between ~10 and 20 Mya, suggesting that they diverged and diversified in isolation during this period around the Pebas mega wetland. After 10 Mya and the transition to the modern configuration of the Amazon River watershed, most speciation within each genus continued to occur within each area. In Osteocephalus, only three species expanded widely across Amazonia (Osteocephalus was probably driven by climatic stability, habitat diversity and the acquisition of new reproductive modes along the Andean foothills and western Amazonia. Our findings add evidence to the importance of major hydrological changes during the Miocene on biotic diversification in Amazonia.

Major historical landscape changes have left significant signatures on species diversification. However, how these changes have affected the build-up and maintenance of Amazonia’s megadiversity continues to be debated. Here, we addressed this issue by focusing on the evolutionary history of a pan-Amazonian toad genus that has diversified throughout the Neogene (Amazophrynella). Based on a comprehensive spatial and taxonomic sampling (286 samples, all nominal species), we delimited operational taxonomic units (OTUs) from mitochondrial DNA sequences. We delimited 35 OTUs, among which 13 correspond to nominal species, suggesting a vast underestimation of species richness. Next, we inferred time-calibrated phylogenetic relationships among OTUs based on complete mitogenomic data, which confirmed an ancient divergence between two major clades distributed in eastern and western Amazonia, respectively. Ancestral area reconstruction analyses suggest that the Andean foothills and the Brazilian Shield region represent the ancient core areas for their diversification. These two clades, probably isolated from one other by lacustrine ecosystems in western Amazonia during the Miocene, display a pattern of northward and eastward dispersals throughout the Miocene‒Pliocene. Given the ecological association of Amazophrynella with non-flooded forests, our results reinforce the perception that ancient Amazonian landscape changes had a major impact on the diversification of terrestrial vertebrates.

Supplemental material for this article can be accessed here: http://dx.doi.org/10.1080/14772000.2022.2089269.; International audience; The Leptodactylus melanonotus species group is an anuran clade widely distributed in the Neotropics. This clade harbours many species that are difficult to identify because of incomplete taxonomic knowledge, ambiguous species boundaries and distribution. Here we expand the understanding of species diversity of this Leptodactylus clade by analysing mtDNA sequences for over 600 individuals, delimiting Operational Taxonomic Units (OTUs), and updating species identifications and distributions by linking sequences to morphotypes and calls. Also, we review the morphological and acoustic traits traditionally used as diagnostic characters of species within this group. The DNA-based species delimitation analyses yielded 57 OTUs. Given that only 19 taxa are currently recognized as valid species, our results suggest the existence of many unnamed species within the L. melanonotus group. After reassessing morphological traits in the group, we concluded that the combined use of dorsolateral fold, upper lip stripe, and belly colouration is sufficiently informative for species identification in most cases, especially when associated with data on geographic distribution and habitat use. Regarding advertisement calls, the patterns of amplitude and frequency modulation, calling rate, and dominant frequency were also informative for species discrimination. Furthermore, we designate a neotype for L. wagneri, for which we also describe the advertisement call, and make comparisons with congeners of the L. melanonotus group, especially with the partially sympatric L. leptodactyloides. Lastly, we name and describe a new species endemic to the Eastern Guiana Shield. Patterns of distribution and habitat use in the L. melanonotus group revealed that sympatric occurrences are more commonly found among distantly related species, whereas allopatric occurrences correspond to closely related ones. Speciation between closely related species of the group seems to be related to ecological divergence (open vs. forest habitats) in parallel with clear morphological and acoustic differentiation.

Several species of Cophomantini are known to have an enlarged prepollex, commonly modified as an osseous spine. We surveyed the osteology and myology of the prepollex and associated elements of 94 of the 190 species of Cophomantini, sampling all genera, except Nesorohyla. Two distinct prepollex morphologies were found: a blade-shaped and a spine-shaped morphology. We described the observed variation in 17 discrete characters to study their evolution in the most inclusive phylogenetic hypothesis for Cophomantini. Both morphologies evolved multiple times during the evolutionary history of this clade, but the origin of the spine-shaped distal prepollex in Boana and Bokermannohyla is ambiguous. The articulation of metacarpal II with the prepollex through a medial expansion of the metacarpal proximal epiphysis is a synapomorphy for Boana. The shape of the curve of the spine, and a large post-articular process of the distal prepollex, are synapomorphies for the Boana pulchella group, the latter being homoplastic in the Bokermannohyla martinsi group. Muscle character states associated with the spine-shaped prepollex are plesiomorphic for Cophomantini. We discuss evolution, function, behaviour and sexual dimorphism related to the prepollical elements. A bony spine is associated with fights between males, but forearm hypertrophy could be more related with habitat than with territorial combat.

Supplemental material for this article can be accessed here: https://doi.org/10.1080/14772000.2022.2130464; International audience; Determining the relative importance of dispersal and vicariance events across neotropical regions is a major goal in biogeography. These events are thought to be related to important landscape changes, notably the transition of Amazonia toward its modern hydrological configuration ca. 10 million years ago. We investigated the spatio-temporal context of the diversification of one of the major lineages of Pristimantis, a widespread and large genus of direct-developing Neotropical frogs. We gathered a spatially and taxonomically extensive sampling of mitochondrial DNA sequences from 754 Pristimantis gr. conspicillatus specimens, which led to delimiting 75 Operational Taxonomic Units (OTUs). Complete mitogenomes of 35 of these OTUs were assembled and collated with two nuDNA loci to reconstruct a time-calibrated phylogeny. We identified five major clades that diverged around the Oligocene-Miocene transition and that are largely restricted to distinct Neotropical regions i.e. Western Amazonia (P. conspicillatus clade), the Brazilian Shield (P. fenestratus clade), the Atlantic Forest (P. ramagii clade), the Guiana Shield (P. vilarsi clade) and the northern Andes (P. nicefori clade). The majority of the diversification events within these clades occurred in-situ from the early Miocene onward. Yet, a few ancient dispersal/vicariance events are inferred to have occurred among trans-Andean forests, the Atlantic Forest, the Brazilian and the Guiana Shields, but almost none in the last 10 Ma. The radical landscape transformations during the Miocene caused by the Andean orogeny and hydrological barriers such as the Pebas System and the subsequent transcontinental configuration of the Amazon drainage is a likely explanation for the isolation of the different clades within the P. gr. conspicillatus.

With 566 species, the neotropical genus Pristimantis is the most speciose vertebrate genus. As a result of its striking diversity, taxonomic reviews remain a challenge. Herein, we present an updated phylogeny of the Pristimantis lacrimosus group and describe a new species from Llanganates and Sangay National Parks. We also report, for the first time, the phylogenetic position of Pristimantis degener, P. eugeniae, P. katoptroides, and P. petersi. Based on our phylogeny, we add two species to the Pristimantis lacrimosus group. Through the integration of molecular and bioacoustic evidence, we describe a new species which was hidden under “Pristimantis petersi”. Pristimantis petersioidessp. nov. is most closely related to Pristimantis petersi and an undescribed species from Peru. It can be distinguished from P. petersi by its advertisement call and large genetic differences (uncorrected p-genetic distances 7.9% to 8.4% for gene 16S). Moreover, the new species and P. petersi are not sister species. We suggest assigning the new species to the Endangered Red List category because it has a small distribution range with deforestation as result of agriculture and other anthropogenic influences.

We conducted a long-term inventory of the herpetofauna of Wildsumaco Wildlife Sanctuary in the eastern part of the Napo Province in Ecuador. This private preserve is about 500 ha in size and is located on the southern slopes of Volcán Sumaco. The preserve contains primary forest, secondary forest, and pasture habitats. Based mostly on nocturnal transect sampling we documented 39 species of amphibians including one species of salamander, two species of caecilians, and 36 species of frogs. Rain frogs (Pristimantis Jiminez de la Espada, 1871) were diverse with 14 species documented. A diverse species assemblage of 45 reptile species was also documented on the preserve. Six amphibian species found were listed by the IUCN Red List. At least three species exhibited substantial geographic range extensions and seven species showed elevational range extensions. We discovered several undescribed species including one salamander, three frogs, one lizard, and one snake.

The outstanding biodiversity of the Guiana Shield has raised many questions about its origins and evolution. Frogs of the genera Adelastes, Otophryne and Synapturanus form an ancient lineage distributed mostly across this region. These genera display strikingly disparate morphologies and life-history traits. Notably, Synapturanus is conspicuously adapted to fossoriality and is the only genus within this group to have dispersed further into Amazonia. Moreover, morphological differences among Synapturanus species suggest different degrees of fossoriality that might be linked to their biogeographical history. Through integrative analysis of genetic, morphometric and acoustic data, we delimited 25 species in this clade, representing a fourfold increase. We found that the entire clade started to diversify ~55 Mya and Synapturanus ~30 Mya. Members of this genus probably dispersed three times out of the Guiana Shield both before and after the Pebas system, a wetland ecosystem occupying most of Western Amazonia during the Miocene. Using a three-dimensional osteological dataset, we characterized a high morphological disparity across the three genera. Within Synapturanus, we further characterized distinct phenotypes that emerged concomitantly with dispersals during the Miocene and possibly represent adaptations to different habitats, such as soils with different physical properties., Agence Nationale de la Recherche (CEBA, ref. ANR-10-LABX-25-01), Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq #140716/2016-5; 305535/2017-0; PQ 302501/2019-3; PQ 303070/2017-0

Molecular phylogenies have yielded strong support for many parts of the amphibian Tree of Life, but poor support for the resolution of deeper nodes, including relationships among families and orders. To clarify these relationships, we provide a phylogenomic perspective on amphibian relationships by developing a taxon-specific Anchored Hybrid Enrichment protocol targeting hundreds of conserved exons which are effective across the class. After obtaining data from 220 loci for 286 species (representing 94% of the families and 44% of the genera), we estimate a phylogeny for extant amphibians and identify gene tree–species tree conflict across the deepest branches of the amphibian phylogeny. We perform locus-by-locus genealogical interrogation of alternative topological hypotheses for amphibian monophyly, focusing on interordinal relationships. We find that phylogenetic signal deep in the amphibian phylogeny varies greatly across loci in a manner that is consistent with incomplete lineage sorting in the ancestral lineage of extant amphibians. Our results overwhelmingly support amphibian monophyly and a sister relationship between frogs and salamanders, consistent with the Batrachia hypothesis. Species tree analyses converge on a small set of topological hypotheses for the relationships among extant amphibian families. These results clarify several contentious portions of the amphibian Tree of Life, which in conjunction with a set of vetted fossil calibrations, support a surprisingly younger timescale for crown and ordinal amphibian diversification than previously reported. More broadly, our study provides insight into the sources, magnitudes, and heterogeneity of support across loci in phylogenomic data sets.[AIC; Amphibia; Batrachia; Phylogeny; gene tree–species tree discordance; genomics; information theory.]

The combination of genetic and phenotypic characters for species delimitation has allowed the discovery of many undescribed species of Neotropical amphibians. In this study, we used DNA sequences (genes 12S, 16S, ND1 and COI) and morphologic, bioacoustic and environmental characters of the Boana semilineata group to evaluate their phylogenetic relationships and assess their species limits. In addition, we included DNA sequences of several species of Boana to explore cryptic diversity in other groups. We found three Confirmed Candidate Species (CCS) within the B. semilineata group. Holotype examination of Hyla appendiculata shows that it is a valid species that corresponds to one of the CCS, which is here transferred to Boana. We describe the two remaining CCS. Our phylogeny highlights a number of secondary but meaningful observations that deserve further investigation: (1) populations of B. pellucens from northern Ecuador are more closely related to B. rufitela from Panama than to other Ecuadorian populations of B. pellucens; (2) we report, for the first time, the phylogenetic relationships of B. rubracyla showing that it is closely related to B. rufitela and B. pellucens; and (3) B. cinerascens and B. punctata form two species complexes consisting of several unnamed highly divergent lineages. Each of these lineages likely represents an undescribed species.

The Osteocephalus buckleyi species group is widely distributed in primary and secondary forests of the Amazon Basin and Guiana Region. Based on integrative analysis, including morphological and genetic data, we estimate the phylogenetic relationships and species boundaries among populations of the Osteocephalus buckleyi group from the Ecuadorian Amazon, focusing on the O. verruciger-O. cannatellai species complex. Our results uncovered the existence of one confirmed candidate species from Sangay National Park and one unconfirmed candidate species. Here, we describe the new species which is morphologically and ecologically distinct from other Osteocephalus species. The new species is unusual because it shows quite distinct morphology, but low genetic distances compared to its closest relatives. Zoobank.org registration LSID: urn:zoobank.org:pub:01F86A33-2D07-4D9E-A8A2-FF35622E3DB9

Species richness in the genus Pristimantis is underestimated due to the existence of morphologically cryptic species. This is worsened by the low sampling effort and the lack of studies using genetic markers. Here, we use molecular and morphological data to determine the phylogenetic relationships of a clade of Pristimantis distributed throughout montane tropical forests in the eastern Andes, from central Ecuador to northern Perú. We name this clade the Pristimantis trachyblepharis species group. Our results show that it comprises nine species, of which four are formally described and five are new. Four of these undescribed species are formally described here. The group is composed of miniaturized species, such as Pristimantis nanus sp. nov., currently the smallest known species of the genus and the smallest vertebrate in Ecuador. As a first approach to understanding the evolutionary origin and implications of body-size reduction in Pristimantis, we here study the phylogenetic signal and evolutionary trends of body size within the genus. We also provide the first record of P. aquilonaris in Ecuador and we show, for the first time, the phylogenetic position of P. albujai, P. aquilonaris, P. minimus and P. trachyblepharis, which are also members of the P. trachyblepharis species group.

We describe a new species of Pristimantis from southern Ecuador, province of Zamora Chinchipe. The new species is closely related to an undescribed species of Pristimantis from Reserva Tapichalaca, Ecuador and with species of a clade historically assigned to the P. unistrigatus species group, such as P. parvillus, P. luteolateralis, P. walkeri, among others. The new species of Pristimantis is a miniaturized new frog (females 17.1±1.1 mm; males 13.2±0.9 mm), characterized by the presence of “› ‹”-shaped scapular folds, with two subconical tubercles on the medial and posterior regions of folds; tympanic membrane and tympanic annulus present but not externally visible; a prominent rostral papilla present; upper eyelid with one elongated conical tubercle; a conical tubercle on heels; groin with orange or yellow spots. The new species of Pristimantis is distributed in a restricted area in the Cordillera del Condor, a highly-diverse mountain range threatened by multiple anthropogenic activities. We recommend assigning the new species to the Endangered IUCN threatened category because it is only known from three nearby localities within mining concessions.

AIM: We analysed elevational and microclimatic drivers of thermal tolerance diversity in a tropical mountain frog clade to test three macrophysiological predictions: less spatial variation in upper than lower thermal limits (Bretts’ heat‐invariant hypothesis); narrower thermal tolerance ranges in habitats with less variation in temperature (Janzen's climatic variability hypothesis); and higher level of heat impacts at lower elevations. LOCATION: Forest and open habitats through a 4,230‐m elevational gradient across the tropical Andes of Ecuador. METHOD: We examined variability in critical thermal limits (CTmax and CTmin) and thermal breadth (TB; CTmax–CTmin) in 21 species of Pristimantis frogs. Additionally, we monitored maximum and minimum temperatures at the local scale (tmax, tmin) and estimated vulnerability to acute thermal stress from heat (CTmax–tmax) and cold (tmin–CTmin), by partitioning thermal diversity into elevational and microclimatic variation. RESULTS: Our results were consistent with Brett's hypothesis: elevation promotes more variation in CTmin and tmin than in CTmax and tmax. Frogs inhabiting thermally variable open habitats have higher CTmax and tmax and greater TBs than species restricted to forest habitats, which show less climatic overlap across the elevational gradient (Janzen's hypothesis). Vulnerability to heat stress was higher in open than forest habitats and did not vary with elevation. MAIN CONCLUSIONS: We suggest a mechanistic explanation of thermal tolerance diversity in elevational gradients by including microclimatic thermal variation. We propose that the unfeasibility to buffer minimum temperatures locally may explain the rapid increase in cold tolerance (lower CTmin) with elevation. In contrast, the relative invariability in heat tolerance (CTmax) with elevation may revolve around the organisms’ habitat selection of open‐ and canopy‐buffered habitats. Secondly, on the basis of microclimatic estimates, lowland and upland species may be equally vulnerable to temperature increase, which is contrary to the pattern inferred from regional interpolated climate estimators.

Microbiome-pathogen interactions are increasingly recognised as an important element of host immunity. While these host-level interactions will have consequences for community disease dynamics, the factors which influence host microbiomes at larger scales are poorly understood. We here describe landscape scale pathogen-microbiome associations within the context of post-epizootic amphibian chytridiomycosis, a disease caused by the panzootic chytrid fungus Batrachochytrium dendrobatidis. We undertook a survey of Neotropical amphibians across altitudinal gradients in Ecuador ~30 years following the observed amphibian declines and collected skin swab-samples which were metabarcoded using both fungal (ITS-2) and bacterial (r16S) amplicons. Our data reveals marked variation in patterns of both B. dendrobatidis infection and microbiome structure that are associated with host life history. Stream breeding amphibians were most likely to be infected with B. dendrobatidis. This increased probability of infection was further associated with increased abundance and diversity of non-Batrachochytrium chytrid fungi in the skin and environmental microbiome. We also show that increased alpha diversity and the relative abundance of fungi is lower in the skin microbiome of adult stream amphibians compared to adult pond breeding amphibians, an association not seen for bacteria. Finally, stream tadpoles exhibit lower proportions of predicted protective microbial taxa than pond tadpoles, suggestive of reduced biotic resistance. Our analyses show that host breeding ecology strongly shapes pathogen-microbiome associations at a landscape scale, a trait that may influence resilience in the face of emerging infectious diseases.

Made available in DSpace on 2021-06-25T12:41:13Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-20 'Investissement d'Avenir' grant Brazilian Fundacao de Amparo a Pesquisa do Estado do Amazonas Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) SENESCYT (Arca de Noe Initiative) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Centro de Estudos de Insetos Sociais (CEIS) The outstanding species richness of Amazonia has fascinated biologists for centuries. However, the records of actual numbers and distribution of species forming its ecosystems are so incomplete that the understanding of the historical causes and regional determinants of this diversity remain speculative. Anuran clades have repeatedly been documented to harbour many unnamed species in this region, notably the Boana albopunctata species group. Considering the documented distribution and the ecology of the species of that group, we hypothesized that it diversified via successive trans-riverine dispersals during the late Miocene and Pliocene, after the formation of the modern Amazon watershed. To test this hypothesis, we gathered an extensive dataset of 16S rDNA sequences sampled throughout Amazonia and a mitogenomic dataset representative of the diversity of the Glade to (1) re-evaluate species boundaries and distributions, and (2) infer the spatio-temporal history of diversification within Amazonia. We delimited 14 Operational Taxonomic Units (OTUs) in an Amazonian Glade, i.e., 75% higher than currently recognized (14 OTUs for eight described species). Combining molecular data with morphological and acoustic data, two new species, Boana courtoisae sp. nov. from the eastern Guiana Shield and Boana eucharis sp. nov. from Southern Amazonia, are described herein. These species belong to a Glade that diversified throughout Amazonia during the last 10 Ma, thus more recently than co-distributed small terrestrial anurans but concomitantly with other more vagile vertebrates. Our time-scaled phylogeny and biogeographic analyses suggest an initial east-west divergence and confirm reciprocal trans-riverine dispersals during the last 5 Ma. The geomorphological evolution of the region and species-specific dispersal ability largely explain these distinct spatio-temporal patterns across anurans. http://www.zoobank.org/zoobank.org:act:4F8ACA9F-F6F1-4605-BD6C-6D4650AACCBE http://www.zoobank.org/zoobank.org:act:51CC7B40-2D6B-4A9E-AF50-AB34D4CE1042 Univ Paul Sabatier, Lab Evolut & Diversite Biol, CNRS, UMR 5174,IRD, Batiment 4R1,118 Route Narbonne, F-31062 Toulouse 9, France Univ Fed Uberlandia, Inst Ciencias Exatas & Nat Pontal, Lab Anuros Neotrop, Ituiutaba, MG, Brazil Univ Estadual Paulista, Dept Biodiversidade, Lab Herpetol, IB, Rio Claro, SP, Brazil Univ Estadual Paulista, Ctr Aquicultura, IB, Rio Claro, SP, Brazil Pontificia Univ Catolica Ecuador, Escuela Biol, Museo Zool, Quito, Ecuador Johannes Gutenberg Univ Mainz, Inst Organism & Mol Evolut, Mainz, Germany Res Inst & Nat Museum Senckenberg, Dept Terr Zool, Frankfurt, Germany Inst Nacl de Pesquisas da Amazonia, Coordenacao Biodiversidade, Manaus, Amazonas, Brazil Univ Sao Paulo, Inst Biociencias, Dept Zool, Sao Paulo, SP, Brazil Univ Fed Amazonas, Dept Genet, Manaus, Amazonas, Brazil Inst Peruano Herpetol, Lima, Peru Univ Estadual Paulista, Dept Biodiversidade, Lab Herpetol, IB, Rio Claro, SP, Brazil Univ Estadual Paulista, Ctr Aquicultura, IB, Rio Claro, SP, Brazil 'Investissement d'Avenir' grant: ANR-10-LABX-25-01 'Investissement d'Avenir' grant: ANR-10-LABX-0041 'Investissement d'Avenir' grant: ANR-11-INBS-0001 Brazilian Fundacao de Amparo a Pesquisa do Estado do Amazonas: FAPEAM10.13039/501100004916062.00962/2018 FAPESP: 2003/10335-8 FAPESP: 2011/50146-6 FAPESP: BIOTA 2013/50297-0 FAPESP: NSF-DEB 1343578 CNPq: 446935/2014-0 CNPq: 300903/2015-4 CNPq: 305169/2019-0 FAPESP: 2017/08489-0 FAPESP: 2013/50741-7 CAPES: 88887.201356/2018-00

We describe through integrative taxonomy a new Amazonian species of leaf-litter toad of the Rhinella margaritifera species group. The new species inhabits open lowland forest in southwest Amazonia in Brazil, Peru, and Bolivia. It is closely related to a Bolivian species tentatively identified as Rhinella cf. paraguayensis. Both the new species and R. paraguayensis share an uncommon breeding strategy among their Amazonian congeners: each breeds in moderate to large rivers instead of small streams or ponds formed by rainwater. The new species is easily differentiated from other members of the R. margaritifera species group by having a strongly developed bony protrusion at the angle of the jaw, a snout–vent length of 63.4–84.7 mm in females and 56.3–72.3 mm in males, well-developed supratympanic crests with the proximal portion shorter than the parotoid gland in lateral view, a divided distal subarticular tubercle on finger III, and multinoted calls composed of groups of 7–9 pulsed notes and a dominant frequency of 1,012–1,163 Hz. Recent studies have shown that the upper Madeira Basin harbors a megadiverse fauna of anurans, including several candidate species. This is the first member of the R. margaritifera species group to be described from this region in recent years, and at least two additional unnamed species await formal description.

Elachistocleis is a Neotropical genus of microhylid frogs with 18 species, most of which occur east of the Andes in South America. Here, we present a new phylogeny of Gastrophryninae and describe and name a new species of Elachistocleis from southern Ecuador—the first to be found west of the Andes and also the first from Ecuador. Our phylogeny is based on DNA sequences of the mitochondrial genes 12S rRNA, 16S rRNA, COI, and the nuclear genes BDNF, cmyc2, H3A, 28S, SIA1, and Tyr. Elachistocleis araios sp. n., is the sister species of all other Elachistocleis. The finding of this taxon highlights the probability of the existence of more Elachistocleis species west of the Andes.

Expeditions to unexplored or little explored places are important for discovering new species and also for collecting new samples (including specimens and tissues for DNA sequencing ) that may help resolve a plethora of taxonomic problems. In the 19th century, several naturalists explored a number of localities in Amazonia, describing species for which type material was deposited, mostly, in European museums of natural history. Some of these types were lost or destroyed in World War II and recent expeditions have focused on sampling new material from the type localities. material from Boana cinerascens, which allowed us to infer phylogenetic relationships of the Boana punctata group (i.e., green Boana), based on DNA sequence data, and to revaluate the status of B. cinerascens and its synonyms. We designate, redescribe and illustrate a neotype for B. cinerascens, which was described by Spix in 1824, from the Municipality of Tefé, State of Amazonas, Brazil. We revalidate, redescribe, and illustrate Hyla granosa gracilis Melin, 1941(= Boana gracilis). Corroborating previous studies, the green Boana were not recovered as a monophyletic group. Boana cinerascens is sister of B. gracilis plus a clade containing B. atlantica + B. punctata (both species not recovered as monophyletic).

Aim: We investigate the spatiotemporal context of the diversification of Allobates, a widespread genus of Amazonian frogs with high species diversity particularly in western Amazonia. We tested if that diversity originated in situ or through repeated dispersals from other Amazonian areas and if this diversification took place during or after the Pebas system, a vast lacustrine system occupying most western Amazonia between 23 and 10 million years ago (Mya). Location: Amazonia. Taxon: Allobates (Anura: Aromobatidae). Methods: We gathered a spatially and taxonomically extensive sampling of mitochondrial DNA sequences from 932 Allobates specimens to delimit Operational Taxonomic Units (OTUs). Complete mitogenomes of these OTUs were assembled to reconstruct a time-calibrated phylogeny used to infer the historical and spatial origin of the Amazonian Allobates lineages. Results: Phylogenetic analyses and ancestral area reconstruction suggested that most of the western Amazonian lineages resulted from in situ diversification and that these events occurred between the inferred origin of the genus (25 Mya) and 10 Mya, with a possible peak between 14 and 10 Mya. Dispersal among areas mostly occurred from western Amazonia towards the Brazilian and the Guiana Shields. Closely related Allobates OTUs display an allopatric pattern of distribution, matching interfluves delimited by modern Amazonian rivers. Main Conclusions: In western Amazonia, diversification of Allobates appears to have been simultaneous with the last stages of the Pebas system (14–10 Mya). Subsequently (within the last 10 Mya), modern Amazonian river courses shaped the distribution pattern of Allobates species and possibly promoted allopatric speciation., This study benefited from an “Investissement d’Avenir” grant managed by the Agence Nationale de la Recherche (CEBA, ref. ANR-10-LABX-25-01; TULIP, ref. ANR-10-LABX-0041; ANAEE-France: ANR-11-INBS-0001). AF and FPW acknowledge the French/Brazilian GUYAMAZON program action (IRD, CNRS, CTG, CIRAD and Brazilian Fundação de Amparo à Pesquisa do Estado do Amazonas-FAPEAM 062.00962/2018) and co-coordinated by A. Fouquet and F. P. Werneck. MTR thanks Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP grant numbers: 2003/10335-8, 2011/50146-6 and NSF-FAPESP Dimensions of Biodiversity Program [grant numbers: BIOTA 2013/50297-0, NSF-DEB 1343578]) and NASA. SRR acknowledges a grant from SENESCYT (Arca de Noé Initiative). FPW thanks CNPq (Productivity Fellowship), FAPEAM, Coordenação de Aperfeiçoamento de Pessoal de Nível Superior-CAPES (Visiting Professor Fellowship) and the L’Oréal-UNESCO For Women In Science Program. AFJ is supported by the Coordenação de Aperfeiçoamento de Pessoal de Nivel Superior-Brasil (CAPES Finance Code: 88882.462010/2019-01). JM is supported by the Ministry of Culture of the Czech Republic (DKRVO 2019-20023/6.VI.b, National Museum Prague, 00023272). PJRK was supported by research grants from the Fonds voor Wetenschappelijk Onderzoek (FWO12A7614N and FWO12A7617N). AJC was supported by Research Program INV-2017-51-1432 from the School of Sciences, Universidad de los Andes. RE was supported by research grants from the Deutsche Forschungsgemeinschaft (DFG ER 589/1-1 & ER 589/2-1).

A new phylogeny for the Pristimantis lacrimosus species group is presented, its species content reviewed, and three new species described from the eastern slopes of the Ecuadorian Andes. Our phylogeny includes, for the first time, samples of P. aureolineatus, P. bromeliaceus, and P. lacrimosus. The morphology of hyperdistal subarticular tubercles is also assessed among 21 species of Pristimantis. The P. lacrimosus species group is composed of 36 species distributed in the Chocó, Guiana, and Amazon regions of tropical South America with a single species reaching Central America. Ancestral area reconstruction indicates that, despite its high diversity in the Amazon region, the P. lacrimosus group originated in the Pacific basin, Chocó region of Ecuador and Colombia. Pristimantis amaguanaesp. nov. is most closely related to P. bromeliaceus. It differs from P. bromeliaceus by being smaller, having transversal dark bands in the hindlimbs (absent or faint in P. bromeliaceus) and the absence of discoidal fold (present in P. bromeliaceus). Pristimantis nankintssp. nov. and P. romeroaesp. nov. are part of a clade of predominantly light-green frogs that includes P. acuminatus, P. enigmaticus, P. limoncochensis, and P. omeviridis. Pristimantis nankintssp. nov. and P. romeroaesp. nov. can be distinguished from all of them by the presence of a dark dorsolateral stripe that borders a light green band on a green background. Hyperdistal tubercles are present in all examined species of the P. lacrimosus species group and its sister clade. Species with hyperdistal tubercles are characterized by having relatively long terminal phalanges and narrow T-shaped expansion at the end of the terminal phalange. We discuss the phylogenetic distribution of these characters and their potential diagnostic significance.

Knowledge on long-term population trends in crocodilians is essential to assess the effectiveness of conservation areas and to guide sustainable management practices. We studied changes in population size of spectacled (Caiman crocodilus) and black caimans (Melanosuchus niger) over a period of 17 yr at Mateococha, a black-water lake located in Cuyabeno Wildlife Reserve, western Amazonia, Ecuador. Using standardized spotlight counts and two mark–recapture surveys, we estimated the population abundance, body size structure, and sex ratio in 1994, 2004, and 2011. The maximum number of C. crocodilus recorded in 1994 (147 individuals; 33 individuals/kilometer [ind/km] of lakeshore) declined by 2004 to 94 individuals (21.1 ind/km) and by 2011 to 63 individuals (14.2 ind/km). The number of M. niger recorded was low but constant (5–7 individuals; 1.1–1.6 ind/km) throughout the study, suggesting that factors causing the decline in C. crocodilus were not related to the M. niger population trend. Large C. crocodilus adults (total length 150–220 cm) were frequent in 1994 but became rare in 2004 and 2011. The sex ratio of captured C. crocodilus was male-biased during all periods. The causes of the population decline are unknown, but available evidence suggests that illegal hunting and habitat degradation are likely culprits despite the protected status of the Cuyabeno Reserve. Our findings question the effectiveness of protected areas to ensure long-term survival of caiman populations in Ecuador.

The genus Dendropsophus is one of the most speciose among Neotropical anurans and its number of described species is increasing. Herein, molecular, morphological, and bioacoustic evidence are combined to assess species limits within D. parviceps, a widely distributed species in the Amazon Basin. Phylogenetic relationships were assessed using 3040 bp sequences of mitochondrial DNA, genes 12S, ND1, and CO1. The phylogeny shows three well-supported clades. Bioacoustic and morphological divergence is congruent with those clades demonstrating that Dendropsophus parviceps is a species complex. Dendropsophus parviceps sensu stricto occurs in the Amazon basin of Ecuador, northern Peru, southern Colombia and northwestern Brazil. It is sister to two previously undescribed species, D. kubricki sp. n. from central Peru and D. kamagarini sp. n. from southern Peru, northeastern Bolivia, and northwestern Brazil. Genetic distances (uncorrected p, gene 12S) between D. parviceps and the new species is 3 to 4%. Dendropsophus kamagarini sp. n. can be distinguished from D. parviceps by having a prominent conical tubercle on the distal edge of the upper eyelid (tubercle absent in D. parviceps). Dendropsophus kubricki sp. n. differs from D. parviceps by having scattered low tubercles on the upper eyelids (smooth in D. parviceps). Dendropsophus parviceps and both new species differ from all their congeners by their small size (adult maximum SVL = 28.39 mm in females, 22.73 mm in males) and by having a bright orange blotch on the hidden areas of the shanks and under arms. The advertisement call of the two new species has lower dominant frequency relative to D. parviceps. Probable speciation modes are discussed. Available evidence indicates that ecological speciation along an elevation gradient is unlikely in this species complex.

Rapid radiation coupled with low genetic divergence often hinders species delimitation and phylogeny estimation even if putative species are phenotypically distinct. Some aposematic species, such as poison frogs (Dendrobatidae), have high levels of intraspecific color polymorphism, which can lead to overestimation of species when phenotypic divergence primarily guides species delimitation. We explored this possibility in the youngest origin of aposematism (3–7 MYA) in poison frogs, Epipedobates, by comparing genetic divergence with color and acoustic divergence. We found low genetic divergence (2.6% in the 16S gene) despite substantial differences in color and acoustic signals. While chemical defense is inferred to have evolved in the ancestor of Epipedobates, aposematic coloration evolved at least twice or was lost once in Epipedobates, suggesting that it is evolutionarily labile. We inferred at least one event of introgression between two cryptically colored species with adjacent ranges (E. boulengeri and E. machalilla). We also find evidence for peripheral isolation resulting in phenotypic divergence and potential speciation of the aposematic E. tricolor from the non-aposematic E. machalilla. However, we were unable to estimate a well-supported species tree or delimit species using multispecies coalescent models. We attribute this failure to factors associated with recent speciation including mitochondrial introgression, incomplete lineage sorting, and too few informative molecular characters. We suggest that species delimitation within young aposematic lineages such as Epipedobates will require genome-level molecular studies. We caution against relying solely on DNA barcoding for species delimitation or identification and highlight the value of phenotypic divergence and natural history in delimiting species.

© 2017 The Authors., Assembly of ecological communities is important for the conservation of ecosystems, predicting perturbation impacts, and understanding the origin and loss of biodiversity. We tested how amphibian communities are assembled by neutral and niche‐based mechanisms, such as habitat filtering. Species richness, β‐diversities, and reproductive traits of amphibians were evaluated at local scale in seven habitats at different elevation and disturbance levels in Wisui Biological Station, Morona‐Santiago, Ecuador, on the foothills of the Cordillera del Kutukú; and at regional scale using 109 localities across evergreen forests of Amazonia and its Andean slopes (0–3,900 m a.s.l.). At local scale, species composition showed strong differences among habitats, explained mainly by turnover. Reproductive modes occurred differently across habitats (e.g., prevalence of direct developers at high elevation, where breeding in ground level water disappears). At regional scale, elevation was the most important factor explaining the changes in species richness, reproductive trait occurrences, and biotic dissimilarities. Species number in all groups decreased with elevation except for those with lotic tadpoles and terrestrial reproduction stages. Seasonality, annual precipitation, and relative humidity partially explained the occurrence of some reproductive traits. Biotic dissimilarities were also mostly caused by turnover rather than nestedness and were particularly high in montane and foothill sites. Within lowlands, geographic distance explained more variability than elevation. Habitat filtering was supported by the different occurrence of reproductive traits according to elevation, water availability, and breeding microhabitats at both scales, as well as other assembly mechanisms based in biotic interactions at local scale. Human‐generated land use changes in Amazonia and its Andean slopes reduce local amphibian biodiversity by alteration of primary forests and loss of their microhabitats and the interaction network that maintains their unique amphibian assemblages with different reproductive strategies., Specimens were collected under research permits 008‐09 IC‐FAU‐DNB/MA and 05‐2011‐Investigacion‐B‐DPMS from the Ministerio del Ambiente of Ecuador. This research was partly supported by projects CGL2011‐30393BOS and CGL2014‐56160‐P of the Spanish Government (PI, I. De la Riva).

Ecnomiohyla tuberculosa is an Amazonian hylid of uncertain phylogenetic position. Herein DNA se- quences of mitochondrial and nuclear genes are used to determine its phylogenetic relationships. New sequences and external morphology of Trachycephalus typhonius are also analyzed to assess the status of Ecuadorian and Peruvian populations. The phylogeny shows unequivocally that Ecnomiohyla tuberculosa is nested within the genus Tepuihyla, tribe Lophiohylini. This position was unexpected because the remain- ing species of Ecnomiohyla belong to the tribe Hylini. To solve the paraphyly of the genus Ecnomiohyla, E. tuberculosa is transferred to the genus Tepuihyla. Comparisons of DNA sequences, external morphology, and advertisement calls between populations of Ecnomiohyla tuberculosa from Ecuador and Peru indicate that the Peruvian population represents an undescribed species. The new species is described and a species Copyright Santiago R. Ron et al.. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. account is provided for Ecnomiohyla tuberculosa. Trachycephalus typhonius is paraphyletic relative to T. cu- nauaru, T. hadroceps, and T. resinifictrix. The phylogenetic position of populations from western Ecuador indicates that they represent a species separate from T. typhonius sensu stricto. We resurrect the name Hyla quadrangulum (Trachycephalus quadrangulum comb. n.) for those populations. Amazonian populations of “T. typhonius” from Ecuador and Peru are genetically and morphologically distinct from T. typhonius sensu stricto and are conspecific with the holotype of Hyla macrotis. Therefore, we also resurrect Hyla macrotis, a decision that results in Trachycephalus macrotis comb. n. Pensoft Publishers

Since 1984 there have been no records of Rhaebo colomai (Hoogmoed, 1985) within the territory of Ecuador. This species was known from 2 localities in the province of Carchi, northwestern Ecuador, and the department of Nariño, southwestern Colombia, which were reported in 1979 and 2015, respectively. We report the recent sightings of R. colomai at 3 new localities in Ecuador and discuss and evaluate this species’ extinction risk and conservation status.

We describe a new species ofPristimantisfrom the montane forest of the Río Zuñag Ecological Reserve, upper basin of the Pastaza River, Ecuador.Pristimantismalliisp. n.is characterized by a snout-vent length of 11.6–21.3 mm in adult males (n= 12), 22.6–34.3 mm in adult females (n= 8), and is compared morphologically and genetically withPristimantismiktosand with other relevant species ofPristimantis. The new species is characterized by having skin on dorsum and flanks shagreen, distinctive scapular folds, snout broadly rounded in dorsal view, upper eyelid bearing one or two subconical tubercles and some rounded tubercles, dorsum and flanks light brown to brown, with irregular dark brown marks bounded by dirty cream and groin with irregular yellowish marks.

We describe a new species of Lynchius from the eastern montane forest of southern Ecuador. We also report the occurrence of L. parkeri in Ecuador, on paramos of Yacuri National Park, near the border with Peru. We used morphological and genetic evidence for the description of the new species and the new report of L. parkeri. Phylogenetic analyses were carried out using both maximum likelihood and Bayesian inference on DNA sequences for mitochondrial and nuclear genes. The phylogeny shows that L. simmonsi is sister to a clade composed of the remaining species of Lynchius and that the new species is sister to L. flavomaculatus. The new species has a prominent and heavily ossified head with noticeably spiculate cranial exostosis that easily distinguishes it from all its congeners. The dorsal region and limbs present several reduced subconical and rounded tubercles and pronounced dermal ridges on the dorsum. We also describe the osteology of the new species based on x-rays of the holotype. Only six species of Lynchius, two known to occur in Ecuador (L. flavomaculatus and L. simmonsi). The description of L. megacephalus sp. n. and new record of L. parkeri double the number of known Lynchius in Ecuador and suggest that the diversity of Ecuadorian and Peruvian Lynchius is still underestimated.

Pristimantis is the most diverse genus of tetrapods comprising 532 described species. It contains a large number of morphologically cryptic species that are being discovered with the assistance of genetic evidence. We use molecular, morphological, bioacoustic, and environmental data to assess the phylogenetic relationships and determine the species within an Andean clade of Pristimantis, which is distributed from central Ecuador to northern Peru. We assign to this clade the name Huicundomantis and propose it as a subgenus. Our results show that Huicundomantis is composed of two large clades which we name as the P.phoxocephalus species group and the P.cryptomelas species group. Huicundomantis is composed of 28 species of which 12 have been described and 16 are new. We describe 11 of these undescribed species. The most effective characters to discriminate among species are DNA sequences, qualitative morphology, and advertisement calls. Morphometric and environmental characters are not very useful to define species limits. We clarify the identity of P.riveti and show that populations from southern Ecuador traditionally ascribed to P.riveti are a new species, P.lutzaesp. nov. We also show that P.prometeii is a junior synonym of P.hampatusami. The current diversity and geographic distribution of Huicundomantis are consistent with a model of allopatric speciation. All species have a restricted distribution range (less than 4330 km2) and are assigned to the Red List categories Data Deficient or threatened with extinction. We provide new reasons to increase conservation efforts for these species and their habitat. Taking our results into account, Pristimantis species richness in Ecuador increases from 211 to 221 species, and the number of species endemic to Ecuador from 119 to 129.

In recent decades, a renewed interest in comparative studies of embryonic ontogeny in anurans is taking place. Toad embryos are often employed as model organisms, and scarce attention has been put on interspecific variations. In this work we analyze the development of transient embryonic and larval structures in 21 species in five genera of Bufonidae. These species vary in their ovipositional mode and the type of environments where the embryos and tadpoles develop, including ponds, streams, and axils of leaves of terrestrial or epiphytic plants. Comparative anatomical studies and sequence heterochrony analyses show that primary morphological variations occur in the morphology at the tail-bud stage, the arrangement and development of the external gills, adhesive gland type and division timing, growth of the dorsal hatching gland on the head, configuration of the oral disc, emergence and development of the hind limbs, and presence of the abdominal sucker. Some of these transformations are best ex...

We describe two new species of frogs of the genus Pristimantis from the eastern slopes of the Ecuadorian Andes, at Parque Nacional Llanganates. The new species are characterized by the spiny appearance typical of several species inhabiting montane forests. Pristimantis yanezi sp. n. is most similar to Pristimantis colonensis and Pristimantis incanus but differs from both in groin coloration and by having smaller tubercles on the upper eyelids, heels, and tarsus. Pristimantis llanganati sp. n. is most similar to Pristimantis eriphus and Pristimantis chloronotus. It can be distinguished from Pristimantis eriphus by the color pattern on the scapular region and by having smaller conical tubercles on the dorsum. Pristimantis chloronotus differs from Pristimantis llanganati sp. n. in having a pair of sinuous paravertebral folds. Both new species occur in a region with few amphibian collections and nothing is known about their abundance and ecology. Therefore, it is recommended to assign them to the Data Deficient Red List category. Updated figures of species richness of Pristimantis among biogeographic regions in Ecuador are also presented. Pristimantis reach their highest diversity in Montane Forests of the eastern versant of the Andes. Its species richness across regions cannot be explained by regional area, elevation, temperature, or precipitation. Political endemism in Pristimantis is higher than that of other terrestrial vertebrates.

General consensus emphasizes that no single biological process can explain the patterns of species' distributions and diversification in the Neotropics. Instead, the interplay of several processes across space and time must be taken into account. Here we investigated the phylogenetic relationships and biogeographic history of tree frogs in the Dendropsophus leucophyllatus species group (Amphibia: Hylidae), which is distributed across Amazonia and the Atlantic rainforests. Using Next Generation Sequencing (NGS) and double digest restriction-site associated DNA (ddRADseq), we inferred phylogenetic relationships, species limits, and temporal and geographic patterns of diversification relative to the history of these biomes. Our results indicate that the D. leucophyllatus species group includes at least 14 independent lineages, which are currently arranged into ten described species. Therefore, a significant portion of species in the group are still unnamed. Different processes were associated to the group diversification history. For instance, the Andes uplift likely caused allopatric speciation for Cis-Andean species, whereas it may also be responsible for changes in the Amazonian landscape triggering parapatric speciation by local adaptation to ecological factors. Meanwhile, Atlantic Forest ancestors unable to cross the dry diagonal biomes after rainforest's retraction, evolved in isolation into different species. Diversification in the group began in the early Miocene, when connections between Atlantic Forest and the Andes (Pacific Dominion) by way of a south corridor were possible. The historical scenario in Amazonia, characterized by several speciation events and habitat heterogeneity, helped promoting diversification, resulting in the highest species diversity for the group. This marked species diversification did not happen in Atlantic Forest, where speciation is very recent (late Pliocene and Pleistocene), despite its remarkable climatic heterogeneity.

Describimos 3 nuevas especies de cutines Pristimantis del subgenero Hypodictyon de la bioregion del Choco de Colombia y Ecuador. Ademas, presentamos una filogenia actualizada del subgenero Hypodictyon en la que reportamos por primera vez la posicion filogenetica de P. calcaratus, P. colomai, P. illotus, P. kuri, P. rosadoi, P. tenebrionis y P. variabilis . Se reviso el contenido de Hypodictyon y sus 2 grupos de especies. Pristimantis afrox sp. nov. se caracteriza por la presencia de un pliegue escapular en forma de ×; pliegue interocular y tuberculo longitudinal en la region interorbital; dedos del pie con pronunciados rebordes cutaneos basales en los dedos II-V; distintiva coloracion inguinal y superficies ocultas de los muslos rojas. Pristimantis chocoensis sp. nov. posee dedo I de la mano igual o ligeramente mas corto que el II; vientre y garganta homogeneamente crema a ligeramente manchados de cafe, pliegue interorbital, rebordes cutaneos laterales presentes, pliegue metatarsal interno y manchas negras hacia la insercion posterior del brazo. Pristimantis cisnerosi sp. nov. presenta distintivos huesos nasales fuertemente convexos y acampanados; narinas protuberantes proyectadas anteriormente; coloracion dorsal cafe oscura y vientre cafe escarlata; tuberculos conicos sobre el parpado y timpano reducido.

The description of Amazophrynella minuta was published in 1941 by the Swedish naturalist Douglas Melin based on material from Taracuá (Amazonas state, Brazil). This description was very brief and based on the morphology of few specimens with diagnostic characters and color variation not well defined. Moreover, the type series is currently in poor state of conservation. Consequently, taxonomic ambiguity surrounds the nominal taxon A. minuta, which hampers the description of many unnamed congeneric species. Herein, we redescribe A. minuta based on recently collected specimens from the type locality, designate a lectotype, formulate a new diagnosis, provide patterns of morphological variation, measurements and body proportions.

A new frog in the genus Pristimantis is described from a cloud forest on the western flanks of the Cordillera del Cóndor and eastern Andean slopes in the province of Zamora Chinchipe, southeastern of Ecuador. We inferred its phylogenetic position using DNA sequences of mitochondrial and nuclear genes. The new species is strongly supported as part of a clade that includes P. ardalonychus, P. cajamarcensis, P. ceuthospilus, P. chalceus, P. minutulus, P. luteolateralis, P. parvillus, P. ockendeni, P. unistrigatus, and P. walkeri. It can be distinguished from all other species from Cordillera del Cóndor and congeneric species by the unique combination of the following characters: (1) iris light blue with black reticulations; (2) skin of dorsum finely shagreen with scattered pustular tubercles and absence of dorsal folds; (3) tympanic membrane and tympanic annulus visible; (4) snout rounded in dorsal and lateral view; (5) upper eyelid bearing two or three enlarged subconical tubercles; (6) cranial crest absent; (7) males lacking vocal sac and slits; and (8) venter uniformly bright red, light red, salmon or orange. The new species is most closely related to P. ardalonychus, P. cajamarcensis, P. ceuthospilus, P. ockendeni and P. unistrigatus. We consider the new species to be Endangered following IUCN criteria because it has been severely affected by large scale open-pit mining in some localities. Currently, the amphibian fauna of the Cordillera del Cóndor and nearby protected areas are threatened by large–scale copper and gold mining projects with devastating effects on ~20 species, including several undescribed ones.

Approximately one-third of amphibian species are experiencing population declines. Among the most affected groups are the Harlequin frogs (Bufonidae: Atelopus), nearly all of which are threatened with extinction. We monitored one of the last known Ecuadorian populations of Atelopus spumarius (Pebas Stubfoot Toad) with a mark–recapture survey between February 2009 and December 2010. We aimed to determine the effect of the fungal pathogen Batrachochytrium dendrobatidis (Bd), previously recorded at the site, on population size and survival. We also analyzed the effect of selective logging which occurred along the transect in April 2010. We tested every individual captured or recaptured for Bd presence using end-point PCR. All 679 Bd swabs (from 356 individuals) were negative, suggesting that Bd did not influence population size and survival. Population size increased during the first 9 months of the study (August 2009–April 2010), from an estimated 47 to 92 individuals, but then decreased by Novembe...

[EN] We review the systematics of the Hypsiboas calcaratus species complex, a group of widely distributed Amazonian hylid frogs. A comprehensive analysis of genetic, morphological, and bioacoustic datasets uncovered the existence of eleven candidate species, six of which are confrmed. Two of them correspond to Hypsiboas fasciatus and Hypsiboas calcaratus and the remaining four are new species that we describe here. Hypsiboas fasciatus sensu stricto has a geographic range restricted to the eastern Andean foothills of southern Ecuador while Hypsiboas calcaratus sensu stricto has a wide distribution in the Amazon basin. Hypsiboas almendarizae sp. n. occurs at elevations between 500 and 1950 m in central and northern Ecuador; the other new species (H. maculateralis sp. n., H. alfaroi sp. n., and H. tetete sp. n.) occur at elevations below 500 m in Amazonian Ecuador and Peru. The new species differ from H. calcaratus and H. fasciatus in morphology, advertisement calls, and mitochondrial and nuclear DNA sequences. Five candidate species from the Guianan region, Peru, and Bolivia are left as unconfirmed. Examination of the type material of Hyla steinbachi, from Bolivia, shows that it is not conspecific with H. fasciatus and thus is removed from its synonymy. © M.A. Caminer, S.R. Ron., [ES] Revisamos la sistemática del complejo de especies Hypsiboas calcaratus, un grupo de ranas hílidas de amplia distribución en la Amazonía. Un análisis exhaustivo de datos genéticos, morfológicos y bioacústicos revelaron la existencia de once especies candidatas, de las cuales seis son confirmadas. Dos de ellas corresponden a Hypsiboas fasciatus e Hypsiboas calcaratus y las cuatro restantes son especies nuevas que describimos aquí. Hypsiboas fasciatus sensu stricto tiene un rango geográfico restringido a las estribaciones orientales de los Andes del sur del Ecuador, mientras que Hypsiboas calcaratus sensu stricto tiene una distribución amplia en la cuenca amazónica. Hypsiboas almendarizae sp. n. se encuentra a alturas entre los 500 y 1950 m en el centro y el norte del Ecuador, mientras que las otras nuevas especies (H. maculateralis sp. n., H. alfaroi sp. n. y H. tetete sp. n.) se encuentran a elevaciones bajo 500 m en la Amazonía de Ecuador y Perú. Las nuevas especies difieren de H. calcaratus e H. fasciatus en morfología, cantos de anuncio y secuencias de ADN mitocondrial y nuclear. Cinco especies candidatas de la región de las Guayanas, Perú y Bolivia quedan como no confirmadas. La examinación del material tipo de Hyla steinbachi indica que no es conespecífica con H. fasciatus y por lo tanto se remueve de su sinonimia.

Foam nests have evolved independently in several amphibian groups as an adaptive response to prevent predation and desiccation in dry environments. Nests are normally laid on ponds, or in underground galleries, humid forest leaf litter or terrestrial bromeliads. They are built when males or females beat a foam precursor associated with the egg masses extruded by the female. The spawning process requires the synchronic actions of the mating pair to obtain a hemispheric nest that protects the offspring. Herein, we describe the spawning behaviour of Engystomops pustulatus based on videos from 13 nesting couples from the lowlands of western Ecuador. Three variables were measured as indicators of male effort: duration of mixing events, duration of resting periods, and number of kicks per mixing event. We consider that not only male physical effort but also female behaviour influences nest structure. We suggest that nest building requires prolonged and intense physical activity by the male as well as th...

We describe the diet of adult and juvenile Engystomops pustulatus from three populations in the Ecuadorian Choco. Analysis of the items recovered from the gastrointestinal tracts of 95 individuals showed that E. pustulatus has a diverse diet. We identified 52 prey types among 1211 items. The numeric niche breadth, as measured by the Simpson's Index, was 5.37 while the volumetric niche breadth was 5.48. Among juveniles at Cerro Blanco we found a high proportion of small prey items, including termites and ants. Larger items, including snails, coleopterans, and isopods, were most frequent in adults at Patricia Pilar and La Mana. We hypothesize that dietary niche breadth is correlated with the presence of teeth in Engystomops. Engystomops pustulatus has teeth and has a more generalist diet than the termite and ant specialist species E. pustulosus, E. petersi, and E. freibergi, which lack teeth.

A new species of Pristimantis is described from Reserva Buenaventura, southern Ecuador, at elevations between 878 and 1082 m. A molecular phylogeny based on nuclear and mitochondrial genes shows that the new species is closely related to P. phoxocephalus, P. riveti, and P. versicolor. The new species differs from them and other morphologically similar congeners in having a low W-shaped dermal ridge in the scapular region, a large conical tubercle on the upper eyelid and on the heel, a thin mid dorsal fold, and a longitudinal lateral fold starting behind the tympanic fold and extending along the anterior two thirds of the flank. The new species inhabits cloud forests in the Pacific slopes of the Andes. © Paul Székely et al. This is an open access article distributed under the terms of the Creative Commons Attribution License.

We present a new phylogeny, based on DNA sequences of mitochondrial and nuclear genes, for frogs of the genus Osteocephalus with emphasis in the Osteocephalus buckleyi species complex. Genetic, morphologic, and advertisement call data are combined to define species boundaries and describe new species. The phylogeny shows strong support for: (1) a basal position of O. taurinus + O. oophagus, (2) a clade containing phytotelmata breeding species, and (3) a clade that corresponds to the O. buckleyi species complex. Our results document a large proportion of hidden diversity within a set of populations that were previously treated as a single, widely distributed species, O. buckleyi. Individuals assignable to O. buckleyi formed a paraphyletic group relative to O. verruciger and O. cabrerai and contained four species, one of which is O. buckleyi sensu stricto and three are new. Two of the new species are shared between Ecuador and Peru (O. vilmae sp. n. and O. cannatellai sp. n.) and one is distributed in the Amazon region of southern Peru (O. germani sp. n.). We discuss the difficulties of using morphological characters to define species boundaries and propose a hypothesis to explain them.

Female mate preferences can favour the evolution of complex secondary sex traits in males. A mechanism increasingly explored to explain the origin of such male traits is sensory exploitation. Under sensory exploitation, female mating preferences are by-products of sensory biases that originate previously (often in nonreproductive contexts). Tungara frogs (Engystomops) have offered a widely known example for this mechanism. Male E. pustulosus make a complex call by adding a chuck to their typical whine call. Previous studies reported that the evolution of complex calls was driven by a female sensory bias that originated in the common ancestor of Engystomops, before the origin of complex calls. Here, I carry out mate choice experiments and new phylogenetic and comparative analyses to reevaluate the evolution of female mate choice and courtship calls in tungara frogs. My results indicate that the chuck and its corresponding female preference have coevolved in a process that is compatible with Fisherian or good genes sexual selection. Character reconstructions show that both the chuck and the female preference have originated multiple times among closely related lineages. I found no support for previously proposed scenarios of sensory exploitation in Engystomops, and the mate choice experiments indicated that increased stimulation of the sensory system by the male courtship signal does not necessarily translate into increased female preference. This finding highlights the significance of central processing in mate choice decisions.

Although dramatic amphibian population declines have been reported worldwide, our understanding of the extent of the declines in Latin America, where amphibian diversity is high, is limited to a few well-documented studies. To better understand the geographic extent of declines, their possible causes, and the measures needed to improve Latin American scientists' ability to research the phenomenon and make effective management recommendations, we convened three regional workshops with 88 Latin American herpetologists and conservationists. Population declines are widespread in Latin America. At least 13 countries have experienced declines, and in 40 cases species are now thought to be extinct or extirpated in a country where they once occurred. Declines or extinctions have affected 30 genera and nine families of amphibians. Most declines have occurred in remote highlands, above 500 m in elevation in Central America and above 1000 m in the Andes. Most documented declines occurred in the 1980s. Of the possible causes studied to date, climate change appears to be important at one site and chytrid fungal disease has been identified at sites in three countries. Although many monitoring studies are currently underway in a variety of habitats, most studies are recent and of short duration. In a signed resolution, workshop participants called for greater collaboration and communication among scientists working in Latin America to understand the geographic extent of population declines and the distribution of possible causal factors. In situ conservation is important to protect habitats, but captive-rearing programs for species subject to imminent extinction are also needed. Better understanding of the taxonomy and natural history of amphibians and more funding for research and monitoring are critical to developing a scientific basis for management action to arrest and reverse population declines.

Female mate choice influences the evolution of male courtship signals and may promote speciation when those sexually selected traits also have a function in species discrimination. Here, we assess interpopulation female mate choice by conducting phonotaxis experiments on a population of the Amazonian frog Engystomops petersi in Puyo, Ecuador. Our results show very strong behavioral isolation relative to 1 of 2 foreign populations. Puyo females strongly discriminate against La Selva in favor of Puyo or Yasuní signals. In contrast, Puyo females do not discriminate against signals from Yasuní, which are similar in frequency. Behavioral isolation was stronger than expected because Puyo females were unable to recognize La Selva courtship signals as belonging to conspecific males. Overall, female mate choices are consistent with male courtship signal differentiation among populations but inconsistent with geographic or genetic distances. Simulations under a null model of undirected evolution (Brownian motion) suggest directional selection on courtship signals at La Selva. Based on our results, we hypothesize that sexual selection and/or reinforcement is driving speciation between E. petersi populations. Copyright 2008, Oxford University Press.

The Rhinella margaritifera species group consists of 17 species of toads distributed in tropical and subtropical South America and eastern Central America. The identity of some of its species is poorly understood and there are numerous undescribed cryptic species. Among them, the status of Rhinella margaritifera is one of the most problematic. Its range includes lowland rainforests separated by the Andes, the Chocoan rainforest to the west and the Amazonian rainforest to the east. This distribution is puzzling because the Andes are an old and formidable barrier to gene flow and therefore should generate vicariant speciation between disjunct lowland populations. Herein we clarify the taxonomy of populations of the Rhinella margaritifera complex from Central America and the Chocó region of South America. The morphological and genetic variation of Rhinella margaritifera was examined from 39 populations from Chocó, 24 from the upper Amazon region of Ecuador, and 37 from Panama, including the holotype of the Panamanian Rhinella alata. Phylogenetic analyses were performed based on mitochondrial genes 12S rRNA, 16S rRNA, and cytochrome c oxidase I (COI) and the nuclear gene Tyrosinase (Tyr). The genetic and morphological data show that Panamanian and Chocoan populations are conspecific. In the phylogeny, populations from Chocó and Panama form a well-supported clade. The morphology of the holotype of Rhinella alata falls within the variation range of Panamanian and Chocoan populations. Based on all this evidence, we assign the populations from western Ecuador and Panama to Rhinella alata and demonstrate that the unusual distribution pattern of “Rhinella margaritifera” on both sides of the Andes was an artifact of incorrectly defined species boundaries.

We describe a new species of Eleutherodactylus from the lowlands of the western Amazon Basin. The new species is referred to the Eleutherodactylus unistrigatus group, lacrimosus assemblage. It differs from other members of the group by having a dorsal olive-green coloration with an interorbital creamy yellow stripe that extends posterolaterally and reaches the level of the sacrum, and low ulnar and tarsal tubercles. The new species inhabits western Amazon tropical rainforests and has been found in arboreal bromeliads by day and on vegetation by night. We discuss the effect of lack of sampling in the forest canopy in our understanding of tropical amphibian communities. Based on work conducted at two localities in Ecuadorian Amazonia, we find that even limited sampling effort in the canopy can greatly improve efficiency of biological inventories.

We present a phylogeny of the Neotropical genus Engystomops (= Physalaemus pustulosus species group) based on sequences of approximately 2.4 kb of mtDNA, (12S rRNA, valine-tRNA, and 16S rRNA) and propose a phylogenetic nomenclature. The phylogeny includes all described taxa and two unnamed species. All analyses indicate that Engystomops is monophyletic and contains two basal allopatric clades. Clade I (Edentulus) includes E. pustulosus and the Amazonian E. petersi + E. cf. freibergi. Clade II (Duovox) includes all species distributed in W Ecuador and NW Peru. Brevivox, a clade of small-sized species is strongly supported within Duovox. Populations of Engystomops pustulosus fall into two well-supported clades, each of which occupies two disjunct portions of the species range. Overall, our phylogeny is congruent with most previous hypotheses. This study is among the few published species-level phylogenies of Neotropical amphibians derived from molecular datasets. A review of the proportion of new species detected by similar studies suggests that the increasing use of molecular techniques will lead to the discovery of a vast number of species of Neotropical amphibians.