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1.
Mol Phylogenet Evol ; 112: 158-173, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28438699

RESUMO

Lack of resolution on species boundaries and distribution can hamper inferences in many fields of biology, notably biogeography and conservation biology. This is particularly true in megadiverse and under-surveyed regions such as Amazonia, where species richness remains vastly underestimated. Integrative approaches using a combination of phenotypic and molecular evidence have proved extremely successful in reducing knowledge gaps in species boundaries, especially in animal groups displaying high levels of cryptic diversity like amphibians. Here we combine molecular data (mitochondrial 16S rRNA and nuclear TYR, POMC, and RAG1) from 522 specimens of Anomaloglossus, a frog genus endemic to the Guiana Shield, including 16 of the 26 nominal species, with morphometrics, bioacoustics, tadpole development mode, and habitat use to evaluate species delineation in two lowlands species groups. Molecular data reveal the existence of 18 major mtDNA lineages among which only six correspond to described species. Combined with other lines of evidence, we confirm the existence of at least 12 Anomaloglossus species in the Guiana Shield lowlands. Anomaloglossus appears to be the only amphibian genus to have largely diversified within the eastern part of the Guiana Shield. Our results also reveal strikingly different phenotypic evolution among lineages. Within the A. degranvillei group, one subclade displays acoustic and morphological conservatism, while the second subclade displays less molecular divergence but clear phenotypic divergence. In the A. stepheni species group, a complex evolutionary diversification in tadpole development is observed, notably with two closely related lineages each displaying exotrophic and endotrophic tadpoles.


Assuntos
Anuros/classificação , Anuros/genética , Variação Genética , Acústica , Animais , Teorema de Bayes , Brasil , DNA Mitocondrial/genética , DNA Ribossômico/genética , Ecossistema , Larva/crescimento & desenvolvimento , Funções Verossimilhança , Filogenia , Análise de Componente Principal , Reprodução , Especificidade da Espécie
2.
Zootaxa ; 3750: 569-86, 2013 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-25113717

RESUMO

We describe a new Pristimantis from French Guiana, northern South America, which is mainly distinguished from known phenotypically related congeners (i.e. species from the polyphyletic unistrigatus species group) occurring at low and middle elevations in the Guiana Shield by the combination of a distinct tympanum, a lower ratio of tibia vs. hand length, a reddish groin region, and a distinct advertisement call consisting of clusters of generally four short notes. The new species inhabits pristine primary forests on the slopes of isolated massifs reaching more than 400 m elevation, and seems not to occur below ca. 200 m above sea level. Such a sharp altitudinal limit suggests a strong influence of thermal variation on the distribution of the species, and therefore a potential sensitivity to climate change. With only nine isolated populations documented so far, the new species should be prioritized for conservation. Historical climate fluctuations during the Quaternary are likely responsible for the distribution pattern of the new species. 


Assuntos
Anuros/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Animais , Anuros/anatomia & histologia , Anuros/fisiologia , Ecossistema , Feminino , Guiana , Masculino , Vocalização Animal
3.
Biodivers Data J ; (3): e5314, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26069439

RESUMO

BACKGROUND: Myotis albescens occurs from Mexico southward to Uruguay and Argentina. The species is known for all South American countries except French Guiana and Chile. NEW INFORMATION: Based on one specimen recently collected in French Guiana we fill part of the gap in the distribution of the species in South America. Myotis albescens occurs in the Guiana Shield with other four congeners, from which it can be distinguished by external and skull traits. As an aid to future identifications, we provide a key to this assemblage.

4.
PLoS One ; 8(6): e67486, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23840717

RESUMO

Although dramatic amphibian declines have been documented worldwide, only few of such events have been quantitatively documented for the tropical forests of South America. This is due partly to the fact that tropical amphibians are patchily distributed and difficult to detect. We tested three methods often used to monitor population trends in amphibian species in a remote lowland tropical forest of French Guiana. These methods are capture-mark-recapture (CMR), estimation of the number of calling males with repeated counts data and distance sampling, and rates of occupancy inferred by presence/absence data. We monitored eight diurnal, terrestrial amphibian species including five Dendrobatidae and three Bufonidae. We found that CMR, the most precise way of estimating population size, can be used only with two species in high density patches where the recapture rate is high enough. Only for one of the species (Dendrobates tinctorius), a low coefficient of variation (CV = 0.19) can be achieved with 15 to 20 capture events. For dendrobatid species with day-calling males, audio surveys yield a better probability of detection with only 8 audio surveys needed; quantitative estimates can be achieved by computing the number of calling males inferred from audio counts or distance sampling analysis. We therefore suggest that an efficient monitoring protocol for Neotropical amphibian species should include a combination of sighting and audio techniques, and we discuss the need of implementing a large-scale monitoring in order to provide a baseline for comparison with future changes.


Assuntos
Anfíbios , Conservação dos Recursos Naturais/métodos , Densidade Demográfica , Dinâmica Populacional , Animais , Biodiversidade , Guiana Francesa , Masculino , Árvores
5.
C R Biol ; 333(1): 48-55, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20176336

RESUMO

The Dipsadidae contains more than 700 extant species belonging to 92 genera and is the largest family of American snakes. In this work, we built a data set including two mitochondrial genes (12S and 16S rRNA) for 125 dipsadid taxa belonging to 59 genera, in order to gain further insights on the phylogenetic relationships of this large group at the subfamilial and generic levels. Among dipsadines, the monotypic genus Nothopsis is the sister-group to Leptodeira. Among xenodontines, the monophyly of seven previously recognized tribes (Alsophiini, Elapomorphini, Hydropsini, Philodryadini, Pseudoboini, Tachymenini and Xenodontini) is confirmed. Among Xenodontini, the genus Liophis is paraphyletic with respect to Erythrolamprus and Umbrivaga and workers should be aware of the inadequacy of the current taxonomy. Finally, the following genera could not confidently be allocated to the above tribes: Caaeteboia, Echinantera and Taeniophallus, Tropidodryas, Manolepis and Pseudalsophis, Xenopholis, Psomophis, Hydrodynastes, Conophis and Crisantophis.


Assuntos
Filogenia , Serpentes/classificação , Serpentes/genética , Animais , DNA Mitocondrial/análise , DNA Mitocondrial/química , Reação em Cadeia da Polimerase , RNA Ribossômico/genética , RNA Ribossômico 16S/genética , Alinhamento de Sequência , Análise de Sequência de DNA
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