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1.
Mol Phylogenet Evol ; 192: 108008, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38181828

RESUMO

Two main landscapes emerge from the Guiana Shield: the highlands to the west called the Pantepui region and the Amazonian lowlands to the east, both harbouring numerous endemic species. With 32 currently recognized species, the genus Anomaloglossus stands out among Neotropical frogs as one that diversified only within the Guiana Shield both in the highlands and the lowlands. We present a time-calibrated phylogeny obtained by using combined mitogenomic and nuclear DNA, which suggests that the genus originates from Pantepui where extant lineages started diversifying around 21 Ma, and subsequently (ca. 17 Ma) dispersed during the Miocene Climatic Optimum to the lowlands of the eastern Guiana Shield where the ability to produce endotrophic tadpoles evolved. Further diversification within the lowlands in the A. stepheni group notably led to an evolutionary reversal toward exotrophy in one species group during the late Miocene, followed by reacquisition of endotrophy during the Pleistocene. These successive shifts of reproductive mode seem to have accompanied climatic oscillations. Long dry periods might have triggered evolution of exotrophy, whereas wetter climates favoured endotrophic forms, enabling colonization of terrestrial habitats distant from water. Acquisition, loss, and reacquisition of endotrophy makes Anomaloglossus unique among frogs and may largely explain the current species diversity. The micro evolutionary processes involved in these rapid shifts of reproductive mode remain to be revealed.


Assuntos
Anuros , Ecossistema , Animais , Anuros/genética , Filogenia , Filogeografia
2.
Nature ; 625(7996): 735-742, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38030727

RESUMO

Noncoding DNA is central to our understanding of human gene regulation and complex diseases1,2, and measuring the evolutionary sequence constraint can establish the functional relevance of putative regulatory elements in the human genome3-9. Identifying the genomic elements that have become constrained specifically in primates has been hampered by the faster evolution of noncoding DNA compared to protein-coding DNA10, the relatively short timescales separating primate species11, and the previously limited availability of whole-genome sequences12. Here we construct a whole-genome alignment of 239 species, representing nearly half of all extant species in the primate order. Using this resource, we identified human regulatory elements that are under selective constraint across primates and other mammals at a 5% false discovery rate. We detected 111,318 DNase I hypersensitivity sites and 267,410 transcription factor binding sites that are constrained specifically in primates but not across other placental mammals and validate their cis-regulatory effects on gene expression. These regulatory elements are enriched for human genetic variants that affect gene expression and complex traits and diseases. Our results highlight the important role of recent evolution in regulatory sequence elements differentiating primates, including humans, from other placental mammals.


Assuntos
Sequência Conservada , Evolução Molecular , Genoma , Primatas , Animais , Feminino , Humanos , Gravidez , Sequência Conservada/genética , Desoxirribonuclease I/metabolismo , DNA/genética , DNA/metabolismo , Genoma/genética , Mamíferos/classificação , Mamíferos/genética , Placenta , Primatas/classificação , Primatas/genética , Sequências Reguladoras de Ácido Nucleico/genética , Reprodutibilidade dos Testes , Fatores de Transcrição/metabolismo , Proteínas/genética , Regulação da Expressão Gênica/genética
3.
R Soc Open Sci ; 10(11): 231443, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38026037

RESUMO

The primary (PSR), secondary (SSR) and adult (ASR) sex ratios of sexually reproducing organisms influence their life histories. Species exhibiting reversed sexual size dimorphism (RSD) may imply a higher cost of female production or lower female survival, thus generating biases in PSR, SSR and/or ASR towards males. The Harpy Eagle is the world's largest eagle exhibiting RSD. This species is found in the Neotropical region and is currently threatened with extinction. We used molecular markers to determine the sex of 309 Harpy Eagles spanning different life stages-eaglets, subadults and adults-from 1904 to 2021 within the Amazon Rainforest and Atlantic Forest. Sex ratios for all life stages revealed a female-biased deviation across all periods and regions. Our results suggest that the population bias towards females is an evolutionary ecological pattern of this species, and SSR and ASR likely emerged from the PSR. This natural bias towards females may be compensated by an earlier sexual maturation age of males, implying a longer reproductive lifespan and a higher proportion of sexually active males. A better understanding of the Harpy Eagle's life history can contribute to understanding sex-role evolution and enable more appropriate conservation strategies for the species.

4.
Primate Biol ; 10(2): 7-11, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37560614

RESUMO

Currently, 15 species of Amazon marmosets (genus Mico) are known to science. The Amazon marmosets occur primarily in southern Brazilian Amazonia, the arc of deforestation, and are among the least studied primates of the neotropics. This is particularly the case for M. acariensis and M. chrysoleucos, both endemic to the Aripuanã-Sucundurí interfluve, south-central Amazonia. Mico acariensis was not studied beyond the species description, and the only information currently available is the pelage colouration of the holotype, inferred coordinates of the type locality, and a field report with two additional localities of occurrence. Regarding M. chrysoleucos, in addition to the species description, there are taxonomic reviews, the report of a second occurrence record, and a study on the species range. We provide here new occurrence records that extend the distribution of M. chrysoleucos; provide new records for and update the distribution of M. acariensis; and propose the existence of a hybrid zone in the Aripuanã-Sucundurí interfluve, i.e. around the known distribution boundaries of M. acariensis, M. chrysoleucos, and M. melanurus, and we also discuss habitat use patterns of Amazon marmosets.

5.
Genes (Basel) ; 14(7)2023 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-37510215

RESUMO

Pitheciines have unique dental specializations among New World monkeys that allow them to feed on fruits with hard pericarps, thus playing a major role as seed predators. The three extant pitheciine genera, Pithecia, Cacajao and Chiropotes, are all endemic to the Amazon region. Because of the uncertainties about interspecific relationships, we reviewed the systematics and taxonomy of the genus Chiropotes. The phylogenetic analyses were performed based on Maximum Likelihood and Bayesian Inference, while species delimitation analyses were carried out using multispecies coalescent methods. In addition, we estimated genetic distances, divergence time and the probable ancestral distribution of this genus. Our results support five species of Chiropotes that emerged during the Plio-Pleistocene. Biogeographic estimates suggest that the ancestor of the current Chiropotes species occupied the endemism areas from Rondônia and Tapajós. Later, subsequent radiation and founder effects associated with the formation of the Amazonian basins probably determined the speciation events within Chiropotes.


Assuntos
Pitheciidae , Platirrinos , Animais , Filogenia , Teorema de Bayes , Frutas
6.
PeerJ ; 11: e15117, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37309369

RESUMO

The Neotropics contain one of the most diverse assemblages of freshwater fishes worldwide. Part of this diversity is shared between the Orinoco and Amazon basins. These basins have been separated for a long time due to the Vaupes Arch, rising between 10-11 Ma. Today, there is only one permanent connection between the Orinoco and Negro (Amazon) basins, known as the Casiquiare Canal. However, alternative corridors allowing fish dispersion between both basins have been proposed. The cardinal tetra (Paracheirodon axelrodi), the most important fish in the ornamental world market, is distributed in both basins. Here we investigated P. axelrodi phylogeography, population structure, and potential routes of migration and connectivity between the two basins. A total of 468 bp of the mitochondrial gene (COI), 555 bp of the nuclear gene fragment (MYH6), and eight microsatellite loci were analyzed. As a result, we found two major genetic clusters as the most likely scenario (K = 2), but they were not discreetly distributed between basins. A gradient of genetic admixture was observed in Cucui and São Gabriel da Cachoeira, between the upper Negro River and the upper Orinoco. Samples from the middle-lower Negro River were highly structured. Cucui (Negro basin) was more similar to the Orinoco than to the rest of the Negro basin populations. However, substructure was also observed by the discriminant analysis, fixation indices and other hierarchichal structure analyses (K = 3 - 6), showing three major geographic clusters: Orinoco, Cucui, and the remaining Negro basin. Unidirectional migration patterns were detected between basins: via Cucui toward Orinoco and via the remaining of the Negro basin toward Orinoco. Results from the Relaxed Random Walk analysis support a very recent origin of this species in the headwater Orinoco basin (Western Guiana Shield, at late Pleistocene) with a later rapid colonization of the remaining Orinoco basin and almost simultaneously the Negro River via Cucui, between 0.115 until about 0.001 Ma. Historical biogeography and population genetic patterns observed here for Cardinal tetra, seem to be better explained by river capture, physical, or ecological barriers than due to the geographic distance.


Assuntos
Characidae , Rios , Animais , Água Doce , Filogeografia
7.
Science ; 380(6648): 906-913, 2023 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-37262161

RESUMO

The rich diversity of morphology and behavior displayed across primate species provides an informative context in which to study the impact of genomic diversity on fundamental biological processes. Analysis of that diversity provides insight into long-standing questions in evolutionary and conservation biology and is urgent given severe threats these species are facing. Here, we present high-coverage whole-genome data from 233 primate species representing 86% of genera and all 16 families. This dataset was used, together with fossil calibration, to create a nuclear DNA phylogeny and to reassess evolutionary divergence times among primate clades. We found within-species genetic diversity across families and geographic regions to be associated with climate and sociality, but not with extinction risk. Furthermore, mutation rates differ across species, potentially influenced by effective population sizes. Lastly, we identified extensive recurrence of missense mutations previously thought to be human specific. This study will open a wide range of research avenues for future primate genomic research.


Assuntos
Evolução Biológica , Variação Genética , Primatas , Animais , Humanos , Genoma , Taxa de Mutação , Filogenia , Primatas/genética , Densidade Demográfica
8.
PeerJ ; 11: e15503, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37361032

RESUMO

Background: Semaprochilodus insignis is a migratory fish of commercial and subsistence importance to communities in the Amazon. Despite the high intensity of exploitation, recent studies have not been carried out to assess the genetic status of its stocks. Methods: This study is the first to estimate genetic diversity and to test the existence of spatial and temporal structuring of S. insignis through sequencing of the mtDNA control region (n = 241) and eight microsatellite loci (n = 180) of individuals sampled at 11 sites distributed in the Brazilian Amazon basin. Results: Results for both markers were congruent, revealing a homogeneous genetic diversity in all the sampled locations, in addition to the absence of spatial and temporal genetic structure, indicating that the species forms a large panmictic population in the Brazilian Amazon. Discussion: Although overfishing does not yet appear to have affected the levels of genetic variability of S. insignis, signals of reduction of the effective population size and a bottleneck provide an early alert to the effects of overfishing. Thus, the ever-decreasing populations may threaten S. insignis in the future. Therefore, it is hoped that the results of this study may contribute to the elaboration of management plans or any other measures that aim at the management and conservation of this species of great importance for the Amazon basin.


Assuntos
Caraciformes , Conservação dos Recursos Naturais , Animais , Pesqueiros , Caraciformes/genética , DNA Mitocondrial/genética , Genética Populacional
9.
J Fish Biol ; 103(2): 247-259, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37013734

RESUMO

The discovery and characterization of cryptic diversity is important for conservation and management, especially for ichthyofauna, whose diversity is underestimated and understudied. Cryptic diversity is especially common in widely distributed species, and Pellona flavipinnis is one such species. Thus, the aim of the present study was to investigate and test whether P. flavipinnis harbours cryptic diversity. In this study we used the COI and control region sequences and microsatellite loci of 86-114 specimens from 11-12 locations throughout the Amazon basin, depending on the molecular marker used. We also included two COI GenBank sequences from the type locality of the species, the Paraná River. The results from COI sequences showed that P. flavipinnis from the Amazon basin presented two spatially structured lineages differentiated from P. flavipinnis from the Paraná River by 10.6%-9.8% (depending on the lineages) and 45 mutational steps. The genetic distance between the Amazon lineages was 2.4% using COI, with high population differentiation values (ФST = 0.8686 and ФST = 0.8483 for COI and control region, respectively). Among the five species delimitation methods employed, three indicated two lineages in P. flavipinnis in the Amazon basin, and all five methods indicated that the Amazonian lineages are different from that of Paraná. Results from microsatellite loci also showed that P. flavipinnis from the Amazon basin is composed of two evolutionary units. The results of 13 morphometric measurements indicated that there are no differences in shape between the P. flavipinnis lineages in the Amazon basin. The present findings suggest that there are two sympatric lineages of P. flavipinnis in the Amazon basin.


Assuntos
Evolução Biológica , Peixes , Animais , Filogenia , Peixes/genética , Brasil , DNA Mitocondrial/genética
10.
PeerJ ; 11: e14526, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36647446

RESUMO

Although the Amazon has the greatest diversity of primates, there are still taxonomic uncertainties for many taxa, such as the species of the Saguinus mystax group. The most geographically broadly distributed and phenotypically diverse species in this group is S. mystax, and its phenotypic diversity has been recognized as three subspecies-S. mystax mystax, S. mystax pileatus and S. mystax pluto-with non-overlapping geographic distributions. In this sense, we carried out an extensive field survey in their distribution areas and used a framework of taxonomic hypothesis testing of genomic data combined with an integrative taxonomic decision-making framework to carry out a taxonomic revision of S. mystax. Our tests supported the existence of three lineages/species. The first species corresponds to Saguinus mystax mystax from the left bank of the Juruá River, which was raised to the species level, and we also discovered and described animals from the Juruá-Tefé interfluve previously attributed to S. mystax mystax as a new species. The subspecies S. m. pileatus and S. m. pluto are recognized as a single species, under a new nomenclatural combination. However, given their phenotypic distinction and allopatric distribution, they potentially are a manifestation of an early stage of speciation, and therefore we maintain their subspecific designations.


Assuntos
Saguinus , Animais , Abelhas
11.
Zootaxa ; 5150(4): 487-515, 2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-36095650

RESUMO

We describe two new species of Rhinella (Anura: Bufonidae) from the department of Loreto, Peru. We integrate morphological and phylogenetic analyses to provide evidence of new species. R. angeli sp. nov. is diagnosable from all congeners by its pronounced fleshy proboscis and R. unapensis sp. nov. by the small size (mean snout-vent length=37.7 4.1 mm) of adult males, snout pointed in dorsal view, nearly acute in lateral view, and small bony protrusion at the angle of jaws among other characters. The two species are allopatric, where the first species is known to be associated inhabits upland (=terra firme) forests, while the second white sand forests (=varillales) around Iquitos city. The two new species represent the 20th and 21st species of the Rhinella margaritifera species group.


Assuntos
Bufonidae , Florestas , Animais , Masculino , Peru , Filogenia , Folhas de Planta
12.
Mol Phylogenet Evol ; 173: 107504, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35577298

RESUMO

Traditionally, Saguinus has been organized into six taxonomic groups: bicolor, inustus, midas, mystax, nigricollis, and oedipus. After recent revisions, taxonomic reclassifications were proposed, including (1) the recognition of Leontocebus as a new genus, and (2) the subdivision of Saguinus into three subgenera. Nonetheless, the contradictory nature of these results reinforces the inconsistency concerning the monophyletic status of tamarins and its interspecific phylogeny. Therefore, in this study, we carried out phylogenetic inferences of Saguinus based on 44 molecular markers, of which 37 were from nuclear DNA and seven from mitochondrial DNA. A final dataset of 24,202 base pairs (bp) was obtained from 60 specimens of all recognized species of Saguinus and, also representatives of two main lineages of Leontocebus. Phylogenetic hypothesis was obtained from Maximum Likelihood (ML) and Bayesian inference (BI) methods. We also construct a Species Tree and a fossil-calibrated multi-locus phylogeny to estimate the time of divergence of Tamarins. Our phylogenetic results validated Leontocebus, or nigricollis group, as monophyletic, and recovered additionally three main clades within Saguinus. Same topology was obtained by the Species Tree. These clades correspond to (1) inustus + mystax groups, (2) oedipus group and (3) bicolor + midas group. Our results show support for a 10.5-million-year-old split between Leontocebus and the remaining Saguinus, followed by two other cladogenetic events, around 9.3 and 7.2 mya, which lead to the rise of the main clades of Saguinus. These phylogenetic data, in concert with the consistent morphological, ecological behavior and biogeographic evidence suggest a new classification for the Amazonian and trans-Andean tamarins. Therefore, we support the validation of Leontocebus as genus and recommend the split of Saguinus into three genera: (1) Tamarinus (inustus and mystax groups), (2) Oedipomidas (oedipus group), and (3) Saguinus (bicolor and midas groups).


Assuntos
Callitrichinae , Cebidae , Animais , Teorema de Bayes , Callitrichinae/anatomia & histologia , Cebidae/genética , DNA Mitocondrial/genética , Filogenia , Saguinus/anatomia & histologia , Saguinus/genética
13.
Mol Ecol ; 31(14): 3888-3902, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35638312

RESUMO

Mitochondrial DNA remains a cornerstone for molecular ecology, especially for study species from which high-quality tissue samples cannot be easily obtained. Methods using mitochondrial markers are usually reliant on reference databases, but these are often incomplete. Furthermore, available mitochondrial genomes often lack crucial metadata, such as sampling location, limiting their utility for many analyses. Here, we assembled 205 new mitochondrial genomes for platyrrhine primates, most from the Amazon and with known sampling locations. We present a dated mitogenomic phylogeny based on these samples along with additional published platyrrhine mitogenomes, and use this to assess support for the long-standing riverine barrier hypothesis (RBH), which proposes that river formation was a major driver of speciation in Amazonian primates. Along the Amazon, Negro, and Madeira rivers, we found mixed support for the RBH. While we identified divergences that coincide with a river barrier, only some occur synchronously and also overlap with the proposed dates of river formation. The most compelling evidence is for the Amazon river potentially driving speciation within bearded saki monkeys (Chiropotes spp.) and within the smallest extant platyrrhines, the marmosets and tamarins. However, we also found that even large rivers do not appear to be barriers for some primates, including howler monkeys (Alouatta spp.), uakaris (Cacajao spp.), sakis (Pithecia spp.), and robust capuchins (Sapajus spp.). Our results support a more nuanced, clade-specific effect of riverine barriers and suggest that other evolutionary mechanisms, besides the RBH and allopatric speciation, may have played an important role in the diversification of platyrrhines.


Assuntos
Genoma Mitocondrial , Rios , Animais , Evolução Biológica , Genoma Mitocondrial/genética , Filogenia , Primatas
14.
Mol Phylogenet Evol ; 173: 107509, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35589052

RESUMO

Bald uakaris, genus Cacajao, are Amazonian primates currently classified as one species and four subspecies based on the patterns of pelage coloration. In this study, we test if their current taxonomy is represented by the phylogenetic relationship of the main lineages retrieved from molecular data. We included, for the first time, all bald uakari taxa in a mitochondrial (cytochrome b) and genome-wide (ddRAD) phylogenetic analyses. We also examined the pattern of pelage colouration in specimens from zoological collections. Having determined the number of lineages using Maximum Likelihood and the species tree using coalescent analyses, we test their divergence time using a Bayesian approach. While the cytochrome b analysis only recovered two clades, the ddRAD analysis supported the reciprocal monophyly of five lineages of bald uakaris, with all clades including only individuals with distinct and exclusive diagnostic phenotypic characters. We found that species diversification in Cacajao occurred during the last 300 Kya and may have been influenced by the formation of rivers and flooded forests in western Amazonia. We propose that the four bald uakari subspecies currently recognised can be upgraded to species level and we describe the white uakaris from the basin of the Rio Tarauacá as a new species.


Assuntos
Pitheciidae , Animais , Teorema de Bayes , Citocromos b/genética , DNA Mitocondrial/genética , Genoma , Filogenia
15.
Mol Phylogenet Evol ; 170: 107426, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35131419

RESUMO

Night monkeys (Aotus, Cebidae) are a widely distributed genus of Neotropical primates with a poorly understood taxonomy and biogeography. The number of species in the genus varies from one to nine, depending on the author, and there are at least 18 known karyotypes, varying from 2n = 46 to 2n = 58. Historically, night monkeys are divided into two species groups: red- and grey-necked groups from south and north of the Amazon-Solimões River, respectively. Here, we used 10 nuclear and 10 mitochondrial molecular markers from a wide taxonomic and geographic sample to infer phylogeny, divergence times, and biogeography of the genus. For phylogenetic reconstruction we used Maximum Likelihood (ML) and Bayesian Inferences (BI). Biogeographic models were generated using the 'BioGeoBEARS' software. We found support for nine taxa of Aotus and rejected the existence of monophyletic "red necked" and "grey necked" species groups. We suggest a taxonomic reclassification of the genus, which is better represented by two clades named northern group, which contains Aotus miconax, A. nancymae, A. trivirgatus, A. vociferans, A. lemurinus, A. griseimembra, A. zonalis, and A. brumbacki, and southern group, which contains A. nigriceps, A. boliviensis, A. infulatus, and A. azarae. The results suggest that the most recent common ancestor of all species of Aotus arose in the central Amazon basin in the Early Pliocene. The evolutionary history of night monkeys was guided by dispersal, vicariance and founder events. The end of the Andean uplift and the subsequent changes in the Amazon landscape, as well as the Amazon-Solimões and Tapajós rivers may have played an important role in the origin and diversification of Aotus, respectively. However, most of the Amazonian rivers seem not to have been geographical barriers to dispersal of night monkeys. The herein named southern group is fruit of a very recent diversification guided by dispersal, crossing the Tapajós, Xingú, Tocantins, and Guapore rivers and reaching the Cerrado in the last 1.6 My.


Assuntos
Aotidae , DNA Mitocondrial , Animais , Aotidae/genética , Teorema de Bayes , Brasil , DNA Mitocondrial/genética , Filogenia , Filogeografia , América do Sul
16.
Mol Phylogenet Evol ; 170: 107442, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35192920

RESUMO

The genus Pipa is a species-poor clade of Neotropical frogs and one of the most bizarre-looking due to many highly derived anatomical traits related to their fully aquatic lifestyle. With their African relatives, they form the Pipidae family, which has attracted much attention, especially regarding its anatomy, reproductive biology, paleontology and biogeography. However, the actual diversity and phylogenetic relationships within Pipa remain poorly understood, and thus so do their historical biogeography and the evolution of striking features, such as the absence of teeth and endotrophy in some species. Using short mtDNA sequences across the distribution of the genus, we identified 15 main lineages (Operational Taxonomic Units - OTUs). This more than doubles the number of the currently seven valid nominal species. Several closely related OTUs do not share nuDNA alleles, confirming species divergence. Time-calibrated phylogenies obtained from mitogenomes and from 10 nuclear loci provide highly similar topologies but strikingly distinct node ages for Pipa. High dN/dS ratios and the variation of substitution rates across the trees suggest a strong effect of saturation on fast evolving positions of mtDNA, producing a substantially shorter stem branch of Pipa. Focusing on the nuDNA topology, we inferred an early Neogene Amazonian origin of the diversification of Pipa, with an initial split between the Guiana-Brazilian Shields and Western Amazonia, a pattern observed in many other co-distributed groups. All the western species are edentate, suggesting a single loss in the genus. Each of these groups diversified further out of Amazonia, toward the Atlantic Forest and toward trans-Andean forests, respectively. These events are concomitant with paleogeographic changes and match patterns observed in other co-distributed taxonomic groups. The two Amazonian lineages have probably independently acquired endotrophic larval development.


Assuntos
Pipidae , Anfíbios/genética , Animais , Teorema de Bayes , DNA Mitocondrial/genética , Filogenia , Filogeografia , Pipidae/genética
17.
PeerJ ; 9: e12443, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34909270

RESUMO

South American freshwater ichthyofauna is taxonomically the most diverse on the planet, yet its diversity is still vastly underestimated. The Amazon basin alone holds more than half of this diversity. The evidence of this underestimation comes from the backlog of morphologically distinct, yet undescribed forms deposited in museum collections, and from DNA-based inventories which consistently identify large numbers of divergent lineages within even well-studied species groups. In the present study, we investigated lineage diversity within the Geophagus sensu stricto species group. To achieve these objectives, we analyzed 337 individuals sampled from 77 locations within and outside the Amazon basin representing 10 nominal and six morphologically distinct but undescribed species. We sequenced the mitochondrial cytochrome c oxidase subunit I (COI) and delimited lineages using four different single-locus species discovery methods (mPTP-15 lineages; LocMin-14 lineages; bGMYC-18 lineages; and GMYC-30 lineages). The six morphologically distinct but undescribed species were also delimited by the majority of the species discovery methods. Five of these lineages are restricted to a single collection site or a watershed and their habitats are threatened by human activities such as deforestation, agricultural activities and construction of hydroelectric plants. Our results also highlight the importance of combining DNA and morphological data in biodiversity assessment studies especially in taxonomically diverse tropical biotas.

18.
Zool Res ; 42(6): 761-771, 2021 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-34643070

RESUMO

The pygmy marmoset, the smallest of the anthropoid primates, has a broad distribution in Western Amazonia. Recent studies using molecular and morphological data have identified two distinct species separated by the Napo and Solimões-Amazonas rivers. However, reconciling this new biological evidence with current taxonomy, i.e., two subspecies, Cebuella pygmaea pygmaea (Spix, 1823) and Cebuella pygmaea niveiventris (Lönnberg, 1940), was problematic given the uncertainty as to whether Spix's pygmy marmoset ( Cebuella pygmaea pygmaea) was collected north or south of the Napo and Solimões-Amazonas rivers, making it unclear to which of the two newly revealed species the name pygmaea would apply. Here, we present the first molecular data from Spix's type specimen of Cebuella pygmaea, as well as novel mitochondrial genomes from modern pygmy marmosets sampled near the type locality (Tabatinga) on both sides of the river. With these data, we can confirm the correct names of the two species identified, i.e., C. pygmaea for animals north of the Napo and Solimões-Amazonas rivers and C. niveiventris for animals south of these two rivers. Phylogenetic analyses of the novel genetic data placed into the context of cytochrome b gene sequences from across the range of pygmy marmosets further led us to re-evaluate the geographical distribution for the two Cebuella species. We dated the split of these two species to 2.54 million years ago. We discuss additional, more recent, subdivisions within each lineage, as well as potential contact zones between the two species in the headwaters of these rivers.


Assuntos
Callitrichinae/classificação , Callitrichinae/genética , DNA Mitocondrial/genética , Filogenia , Distribuição Animal , Animais , Brasil , Especificidade da Espécie
19.
Sci Rep ; 11(1): 15665, 2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-34341361

RESUMO

Amazonia has the richest primate fauna in the world. Nonetheless, the diversity and distribution of Amazonian primates remain little known and the scarcity of baseline data challenges their conservation. These challenges are especially acute in the Amazonian arc of deforestation, the 2500 km long southern edge of the Amazonian biome that is rapidly being deforested and converted to agricultural and pastoral landscapes. Amazonian marmosets of the genus Mico are little known endemics of this region and therefore a priority for research and conservation efforts. However, even nascent conservation efforts are hampered by taxonomic uncertainties in this group, such as the existence of a potentially new species from the Juruena-Teles Pires interfluve hidden within the M. emiliae epithet. Here we test if these marmosets belong to a distinct species using new morphological, phylogenomic, and geographic distribution data analysed within an integrative taxonomic framework. We discovered a new, pseudo-cryptic Mico species hidden within the epithet M. emiliae, here described and named after Horacio Schneider, the pioneer of molecular phylogenetics of Neotropical primates. We also clarify the distribution, evolutionary and morphological relationships of four other Mico species, bridging Linnean, Wallacean, and Darwinian shortfalls in the conservation of primates in the Amazonian arc of deforestation.


Assuntos
Callitrichinae , Conservação dos Recursos Naturais , Agricultura , Animais , Brasil , Callithrix , Ecossistema , Filogenia
20.
Zootaxa ; 4933(3): zootaxa.4933.3.1, 2021 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-33756784

RESUMO

Boana hobbsi is a poorly known hylid frog currently placed within the Boana punctata group. Yet, morphological, ecological and bioacoustic traits do not support this placement, with no molecular data being available to date to test this hypothesis. Based on newly collected mitochondrial DNA sequences, morphological data review and field observations, we provide new insight into the phylogenetic relationships, morphological variations and geographic distribution of B. hobbsi. Our findings reveal that B. hobbsi is nested (with strong support) within the Boana benitezi group, recovering once more a polyphyletic Boana punctata group. Supported by this new genetic, morphological and ecological evidence, we propose a new taxonomic arrangement which includes B. hobbsi as a member of the Boana benitezi group. Furthermore, we emphasize the importance of conducting biological inventories in remote Amazonian areas, where many taxonomic and geographic knowledge gaps persist with regards to Amphibian diversity.


Assuntos
Anuros , DNA Mitocondrial , Animais , Anuros/genética , DNA Mitocondrial/genética , Fenótipo , Filogenia
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