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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: 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.

International audience; Understanding the neural principles governing taste perception in species that bear economic importance or serve as research models for other sensory modalities constitutes a strategic goal. Such is the case of the honey bee (Apis mellifera), which is environmentally and socioeconomically important, given its crucial role as pollinator agent in agricultural landscapes and which has served as a traditional model for visual and olfactory neurosciences and for research on communication, navigation, and learning and memory. Here we review the current knowledge on honey bee gustatory receptors to provide an integrative view of peripheral taste detection in this insect, highlighting specificities and commonalities with other insect species. We describe behavioral and electrophysiological responses to several tastant categories and relate these responses, whenever possible, to known molecular receptor mechanisms. Overall, we adopted an evolutionary and comparative perspective to understand the neural principles of honey bee taste and define key questions that should be answered in future gustatory research centered on this insect.

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

Amazonia harbours a vast biotic and ecological diversity, enabling investigation of the effects of microevolutionary processes and environmental variation on species diversification. Integrative approaches combining phenotypic and genetic variation can improve our knowledge on diversification processes in megadiverse regions. Here, we investigate the influence of environmental and geographic variation on the genetic and morphological differentiation in the Amazonian Boana calcarata-fasciata (Anura: Hylidae) species complex. We analysed the variation of one mtDNA gene from individuals of different forest environments, and assessed their phylogenetic relationships and species limits to define the lineages to perform a phenotypic-environmental approach. We collected morphological data (head shape and size) using 3D models and investigated the phylogenetic signal, evolutionary model and influence of environmental variables on morphology. We verified associations between environmental and geographical distances with morphological and genetic variation using distance-based redundancy analyses and Mantel tests. We found an even higher cryptic diversity than already recognized within the species complex. Body size and head shape varied among specimens, but did not present phylogenetic signal, diverging under a selective evolutionary model. Our results show that diverse factors have influenced morphological and genetic variation, but environmental conditions such as vegetation cover, precipitation and climate change velocity influenced morphological diversification. Possible population-level mechanisms such as parallel morphological evolution or plastic responses to similar environments could account for such patterns in these typical Amazonian treefrogs.

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

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).