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1.
Cladistics ; 37(1): 73-105, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-34478175

RESUMO

The relationships of the hyline tribe Dendropsophini remain poorly studied, with most published analyses dealing with few of the species groups of Dendropsophus. In order to test the monophyly of Dendropsophini, its genera, and the species groups currently recognized in Dendropsophus, we performed a total evidence phylogenetic analysis. The molecular dataset included sequences of three mitochondrial and five nuclear genes from 210 terminals, including 12 outgroup species, the two species of Xenohyla, and 93 of the 108 recognized species of Dendropsophus. The phenomic dataset includes 46 terminals, one per species (34 Dendropsophus, one Xenohyla, and 11 outgroup species). Our results corroborate the monophyly of Dendropsophini and the reciprocal monophyly of Dendropsophus and Xenohyla. Some species groups of Dendropsophus are paraphyletic (the D. microcephalus, D. minimus, and D. parviceps groups, and the D. rubicundulus clade). On the basis of our results, we recognize nine species groups; for three of them (D. leucophyllatus, D. microcephalus, and D. parviceps groups) we recognize some nominal clades to highlight specific morphology or relationships and facilitate species taxonomy. We further discuss the evolution of oviposition site selection, where our results show multiple instances of independent evolution of terrestrial egg clutches during the evolutionary history of Dendropsophus.


Assuntos
Anuros/classificação , Anuros/genética , Filogenia , Animais , Núcleo Celular/genética , Genes Mitocondriais , RNA Ribossômico 16S , Análise de Sequência de DNA
2.
Syst Biol ; 70(1): 49-66, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-32359157

RESUMO

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.].


Assuntos
Fósseis , Genômica , Animais , Anuros , Humanos , Filogenia
3.
Zootaxa ; 4779(3): zootaxa.4779.3.2, 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-33055776

RESUMO

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.


Assuntos
Anuros , Animais , Filogenia , RNA Ribossômico 16S
5.
Mol Phylogenet Evol ; 150: 106877, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32512194

RESUMO

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.


Assuntos
Anuros/classificação , Animais , Anuros/genética , Biodiversidade , Bases de Dados Genéticas , Filogenia , Floresta Úmida , América do Sul , Especificidade da Espécie
6.
Zootaxa ; 4750(1): zootaxa.4750.1.1, 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-32230050

RESUMO

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).


Assuntos
Anuros , Animais , Sequência de Bases , Filogenia , Análise de Sequência de DNA
7.
Cladistics ; 36(3): 301-321, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-34618959

RESUMO

Alopoglossidae is a family of Neotropical lizards composed of 23 species allocated in two genera (Alopoglossus and Ptychoglossus). There is a lack of knowledge about the phylogenetic relationships and systematics of this family. Published phylogenies that include alopoglossid species have very low taxon coverage within the family, and are usually based on limited character sampling. Considering these shortcomings, we infer the phylogenetic relationships of Alopoglossidae-including all but one species in the family-based on the combined analyses of DNA sequences and morphological characters. We use four loci (the mitochondrial 12S, 16S and ND4; the nuclear C-mos) and a matrix of 143 phenotypic characters from scutellation, tongue morphology, hemipenis morphology, and osteology. The dataset is analyzed with Maximum Parsimony, with four alternative weighting schemes: three under Extended Implied Weighting, and one with equal weighting. The respective resulting topologies are compared in a sensitivity analysis framework. Our analyses support the paraphyly of Ptychoglossus, with Alopoglossus nested within it. We provide an updated classification for the family, where Ptychoglossus Boulenger, 1890 is considered a junior synonym of Alopoglossus Boulenger, 1885.


Assuntos
Lagartos/classificação , Lagartos/genética , Animais , Feminino , Genótipo , Masculino , Filogenia , Análise de Sequência de DNA
9.
Mol Phylogenet Evol ; 130: 198-210, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30347238

RESUMO

Chiasmocleis is the most species-rich genus of Neotropical microhylids. Herein, we provide the first comprehensive multilocus phylogeny for the genus, including all but 3 of the 34 recognized species and multiple individuals per species. We discuss cryptic speciation, species discovery, patterns of morphological evolution, and provide a historical biogeographic analysis to account for the current distribution of the genus. Diversification of Chiasmocleis from other New World microhylids began during the Eocene, app. 40 mya, in forested areas, and current diversity seems to be a product of recurrent connections between the Atlantic Forest and Amazonia. Small-sized species evolved independently three times in Chiasmocleis. Furthermore, the extremely small-bodied (i.e. miniaturized) species with associated loss of digits, phalanges, and pectoral girdle cartilages evolved only once and are restricted to Amazonia. Using the phylogeny, we recognized three subgenera within Chiasmocleis: Chiasmocleis Méhely, 1904, Relictus subg. nov., and Syncope Walker, 1973. The recognition of the subgenus Syncope informs future research on patterns of miniaturization in the genus, and the subgenus Relictus highlights isolation of an endemic and species-poor lineage to the Atlantic Forest, early (about 40 mya) in the history of Chiasmocleis.


Assuntos
Anuros/anatomia & histologia , Anuros/classificação , Florestas , Filogenia , Animais , Anuros/genética , Brasil
10.
Anat Rec (Hoboken) ; 302(7): 1074-1092, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30471212

RESUMO

In recent years, major changes have been proposed for the phylogenetic relationships within the Gymnophthalmoidea, including the description of Alopoglossidae. Recent studies relied primarily on molecular data and have not accounted for evidence from alternative sources, such as morphology. In this study, we provide a detailed bone-by-bone description of the skull of Ptychoglossus vallensis and compare this species with other gymnophthalmoideans. The description was based on 10 cleared-and-stained specimens, four disarticulated skulls, and computed microtomography data of P. vallensis. Most recent phylogenetic hypothesis for the Gymnophthalmoidea was used as a framework to compare the skull of P. vallensis with other species of the Alopoglossidae, Gymnophthalmidae, and Teiidae. Marked similarities between alopoglossids and gymnophthalmids were observed in contrast to teiids, probably due to convergence generated by miniaturization. We also qualitatively analyzed the kinesis of the skull of P. vallensis concluding that is highly akinetic, a trait commonly evolved in fossorial, primarily burrowing squamates. We also describe one unique osteological feature for Alopoglossidae that is not known in any other squamate group. Anat Rec, 302:1074-1092, 2019. © 2018 Wiley Periodicals, Inc.


Assuntos
Variação Biológica da População , Lagartos/anatomia & histologia , Crânio/anatomia & histologia , Animais , Lagartos/classificação , Filogenia , Crânio/diagnóstico por imagem , Microtomografia por Raio-X
11.
Zootaxa ; 4532(2): 203-230, 2018 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-30647363

RESUMO

We describe and name the second species of Phyzelaphryne (Brachycephaloidea, Eleutherodactylidae), from northwestern Brazilian Amazonia. Phyzelaphryne nimio sp. nov. is distinguished from its only congener, Phyzelaphryne miriamae, by its smaller body size and the anatomy of the carpal and metacarpal regions, with relatively larger (sometimes fused) supernumerary carpal and metacarpal tubercles. Molecular phylogenetic analyses based on fragments of the mitochondrial genes 16S rRNA and COI suggest that the currently known distribution of the species is restricted to its type locality and other areas within Estação Ecológica Juami-Japurá, state of Amazonas, Brazil. Based on molecular, morphological and bioacoustic evidence, we assigned other specimens recently collected in Parque Nacional do Jaú, state of Amazonas, Brazil, to P. miriamae, extending the species' known geographic distribution north of the Amazon River.


Assuntos
Anuros , Rios , Animais , Anuros/genética , Brasil , Filogenia , RNA Ribossômico 16S
12.
Mitochondrial DNA A DNA Mapp Seq Anal ; 29(7): 1108-1114, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29216781

RESUMO

The integration of approaches that allow the incorporation of stochasticity of gene histories with phylogenetic methods resulted in new approaches for the old issue of species delimitation. Nevertheless, coalescent methods seem problematic for taxa with large effective population size and shallow temporal diversification (like marine fishes). Here, we investigate the performance of single-locus (cytochrome oxidase 1, commonly used in DNA barcoding initiatives) methods for molecular species delimitation in snappers of Lutjaninae from the Western Atlantic and Pacific Eastern. Our results show incongruences among methods. ABGD, PTP and mPTP trend towards a lower number of estimated species. Phylogenetic-coalescent methods with single threshold were majority congruent for a same number of lineages. On the other hand, algorithms with multiple thresholds tend to estimate a higher number of potential species. We do not endorse the use of single-locus for species delimitation, but we do reinforce that single-locus data is sufficient to flag many problems.


Assuntos
Código de Barras de DNA Taxonômico/métodos , Perciformes/genética , Filogenia , Polimorfismo Genético , Animais , Código de Barras de DNA Taxonômico/normas , Complexo IV da Cadeia de Transporte de Elétrons/genética , Proteínas de Peixes/genética , Haplótipos , Perciformes/classificação
13.
Mol Phylogenet Evol ; 111: 56-64, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28336422

RESUMO

Peloso et al. (2015: PELOSO) published a comprehensive phylogenetic study of the frog family Microhylidae, which resulted in the discovery that several taxa were not monophyletic. To remedy this, a series of nomenclatural changes were proposed (several generic synonymies and two new subfamilies named). A recent study published in this journal by Scherz et al. (2016: SCHERZ), provided a novel phylogeny for the Malagasy subfamily Cophylinae. SCHERZ dispute the analyses and taxonomic conclusions of PELOSO. Their study is, however, based on substantial reduction of data from the PELOSO study, limited addition of new data, and different analytical methods. In spite of the fact that their own results are consistent with the taxonomy of PELOSO, SCHERZ reject that conservative taxonomy and suggest the revalidation of Platypelis (from the synonymy of Cophyla), the revalidation of Stumpffia (from the synonymies of Rhombophryne), and the creation of at least two new genera (only one named therein). In doing so, SCHERZ accept the recognition of likely paraphyletic taxa, with Stumpffia paraphyletic in their parsimony analysis. Herein, we provide a response to several points raised in SCHERZ: (1) we discuss issues with their interpretation (and selective use) of available phylogenetic and phenotypic evidence; (2) and provide a new phylogenetic analysis of all the data in PELOSO and SCHERZ combined. In the new analysis Stumpffia is paraphyletic with respect to Rhombophryne, whereas Cophyla and Platypelis are both monophyletic and sister taxa. We provide a case for the use of the taxonomy suggested in PELOSO.


Assuntos
Anuros/classificação , Filogenia , Terminologia como Assunto , Animais , Sequência Consenso , Funções Verossimilhança
14.
Zootaxa ; 4085(1): 63-102, 2016 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-27394289

RESUMO

The Leptolalax applebyi group of Asian leaf-litter frogs currently comprises four species of particularly small-bodied (<40 mm SVL) species distributed in the Central Highlands of Vietnam and northeastern Cambodia. In addition to their small size, the group is characterized by their morphological and genetic similarities, as well as their breeding habitat at headwaters of small mountain streams and seeps. A recent study suggested that at least two-thirds of the diversity of the group remained hidden within morphologically cryptic lineages. We expand upon the molecular, morphometric, and acoustic data and formally delineate and describe five of these lineages as distinct species: Leptolalax ardens sp. nov., Leptolalax kalonensis sp. nov., Leptolalax pallidus sp. nov., Leptolalax maculosus sp. nov., and Leptolalax tadungensis sp. nov. Due to habitat loss, the current ranges of these species are likely to be a fraction of their historical extent and under continued threat from deforestation.


Assuntos
Anuros/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Anuros/anatomia & histologia , Anuros/crescimento & desenvolvimento , Anuros/fisiologia , Tamanho Corporal , Camboja , Ecossistema , Feminino , Masculino , Tamanho do Órgão , Vietnã , Vocalização Animal
16.
Cladistics ; 32(2): 113-140, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34732021

RESUMO

Despite considerable progress in unravelling the phylogenetic relationships of microhylid frogs, relationships among subfamilies remain largely unstable and many genera are not demonstrably monophyletic. Here, we used five alternative combinations of DNA sequence data (ranging from seven loci for 48 taxa to up to 73 loci for as many as 142 taxa) generated using the anchored phylogenomics sequencing method (66 loci, derived from conserved genome regions, for 48 taxa) and Sanger sequencing (seven loci for up to 142 taxa) to tackle this problem. We assess the effects of character sampling, taxon sampling, analytical methods and assumptions in phylogenetic inference of microhylid frogs. The phylogeny of microhylids shows high susceptibility to different analytical methods and datasets used for the analyses. Clades inferred from maximum-likelihood are generally more stable across datasets than those inferred from parsimony. Parsimony trees inferred within a tree-alignment framework are generally better resolved and better supported than those inferred within a similarity-alignment framework, even under the same cost matrix (equally weighted) and same treatment of gaps (as a fifth nucleotide state). We discuss potential causes for these differences in resolution and clade stability among discovery operations. We also highlight the problem that commonly used algorithms for model-based analyses do not explicitly model insertion and deletion events (i.e. gaps are treated as missing data). Our results corroborate the monophyly of Microhylidae and most currently recognized subfamilies but fail to provide support for relationships among subfamilies. Several taxonomic updates are provided, including naming of two new subfamilies, both monotypic.

17.
Zootaxa ; 3881(4): 341-61, 2014 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-25543640

RESUMO

We describe Dendropsophus ozzyi sp. nov., a new species of treefrog, tentatively included in the Dendropsophus microcephalus Group and most notably diagnosed by the presence of pointed fingers and an advertisement call with a very high dominant frequency. The new species is known from three localities in the Brazilian Amazon forest, two on western State of Pará and one (the type locality) in eastern State of Amazonas (03°56'50"S and 58°26'36"W, 45 m a.s.l.).


Assuntos
Anuros/anatomia & histologia , Anuros/classificação , Vocalização Animal , Distribuição Animal , Animais , Anuros/fisiologia , Brasil , Ecossistema , Feminino , Masculino , Comportamento Sexual Animal , Especificidade da Espécie
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