CNRS Guyane USR3456

Cayenne, French Guiana

CNRS Guyane USR3456

Cayenne, French Guiana

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Fouquet A.,CNRS Guyane USR3456 | Courtois E.A.,CNRS Guyane USR3456 | Baudain D.,25 lot. Emilio Pascal | Souza S.M.,University of Sao Paulo | And 2 more authors.
Journal of Tropical Ecology | Year: 2015

Among the hypotheses formulated to explain the origin of Amazonian biodiversity, two (the riverine-barrier and the river-refuge hypotheses) focus on the role that rivers play as biotic barriers promoting speciation. However, empirical results have both supported and refuted these hypotheses. This is likely due, at least in part, to river-specific hydrologic characteristics and the biology of the focal species. The rivers of the Guiana Shield represent a model system because they have had more stable courses over time than those of the western Amazon Basin, where most tests of riverine barrier effects have taken place. We tested whether life-history traits (body size, habitat and larval development), expected to be important in determining dispersal ability, of 28 frog species are associated with genetic structure and genetic distances of individuals sampled from both banks of the Oyapock River. Thirteen of these species displayed genetic structure consistent with the river acting as a barrier to dispersal. Surprisingly, body size was not correlated with trans-riverine population structure. However, leaf-litter dwellers and species lacking free-living tadpoles were found to exhibit higher river-associated structure than open habitat/arboreal species and those with exotrophic tadpoles. These results demonstrate that rivers play an important role in structuring the genetic diversity of many frog species though the permeability of such riverine barriers is highly dependent on species-specific traits. © Cambridge University Press 2015.


Lourenco-De-Moraes R.,State University of Maringá | Ferreira R.B.,Utah State University | Fouquet A.,CNRS Guyane USR3456 | Bastos R.P.,Federal University of Goais
Zootaxa | Year: 2014

The genus Adelophryne is composed of diminutive frogs occurring in northern Amazonia and the Atlantic Forest. Herein we describe a new species of Adelophryne found in the leaf litter of primary and secondary forests in the mountainous region of Espírito Santo state, southeastern Brazil. The new species is characterized by its small body size, two phalanges in the finger IV, and a glandular ridge line that runs from the posterior part of eye to the insertion of the forelimb. This species is sensitive to edge effect and conversion of native forest into coffee and Eucalyptus plantations and may be listed as Endangered (EN) under B1ab(iii) criteria of the IUCN Red List. Copyright © 2014 Magnolia Press.


Fouquet A.,CNRS Guyane USR3456 | Pineau K.,Biotope | Rodrigues M.T.,University of Sao Paulo | Mailles J.,Direction de lEnvironnement de lAmenagement et du Logement de la Martinique | And 3 more authors.
Systematics and Biodiversity | Year: 2013

Amphibian faunas of the Lesser Antilles are depauperate, with only a few species being endemic and generally threatened. Allobates chalcopis from the island of Martinique is a particularly enigmatic case being the only known dendrobatid endemic to an oceanic island. This species has previously been suggested as being introduced to Martinique. The question of its true origin remained unresolved because no individuals were found since its formal description in the 1990s. Twenty years after the last observation of the species, we succeeded in finding an isolated population of Allobates chalcopis in Martinique. The rediscovery allowed us to investigate the species' phylogenetic position, confirming that it is nested within a clade of lowland Amazonian Allobates but nonetheless distantly related to any known species of the group. The arrival of the species in Martinique likely corresponds to an overseas dispersal from South America during the late Miocene, as previously hypothesized for Bothrops lanceolatus and Leptodactylus fallax; two other species endemic to Martinique and surrounding islands. However, the species was not found in its type locality 500 m a.s.l. but 300 m higher in altitude, in herbaceous areas of the summit of Montagne Pelée. The possible range reduction and population decline in combination with the evidence of endemicity of the species highlights the need for a reassignment of the current Red List status. Furthermore, a refined conservation strategy is needed to guarantee the long-term viability of Allobates chalcopis in its native range. © 2013 The Natural History Museum.


Fouquet A.,CNRS Guyane USR3456 | Martinez Q.,CNRS Guyane USR3456 | Courtois E.A.,CNRS Guyane USR3456 | Dewynter M.,Biotope | And 6 more authors.
Zootaxa | Year: 2013

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. © 2013 Magnolia Press.


PubMed | Impasse Jean Galot, CNRS Guyane USR3456, Biotope, Pointe Maripa and Royal Belgian Institute Of Natural Sciences
Type: | Journal: Zootaxa | Year: 2014

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.


Fouquet A.,CNRS Guyane USR3456 | Martinez Q.,CNRS Guyane USR3456 | Zeidler L.,University of California at Berkeley | Courtois E.A.,CNRS Guyane USR3456 | And 6 more authors.
Zootaxa | Year: 2016

We used molecular and morphological data to investigate the hidden diversity within the Hypsiboas semilineatus species group, and more specifically within H. geographicus, an allegedly widespread species in northern South America. As a result, the identity of H. geographicus was clarified, several candidate species were detected and one of them, from the eastern Guiana Shield, is described herein as a preliminary step to resolve the taxonomy of the group. Hypsiboas diaboli-cus sp. nov. is mainly distinguished from closely-related species by an acuminate snout in lateral view, well-developed webbing between fingers and toes, and unspotted carmine/crimson colouration on the concealed surfaces of legs, feet and hands in life. The tadpole of the new species is described and is characterized by a large A-2 gap, a mostly single row of large marginal papillae, and a dark brown to black colouration. We also describe the advertisement call of the new species, which is defined as a soft call consisting of short clusters of 2-3 chuckles with a dominant frequency ranging between 1.11-1.19 kHz. Hypsiboas diabolicus sp. nov. is currently known only from the eastern Guiana Shield, and is probably endemic to that region. The new species' range overlaps broadly with another candidate species referred to as H. aff. semi-lineatus 1. Our preliminary results stress out a high cryptic diversity in that species group and the need for a formal rede-scription of Hypsiboas geographicus based on more topotypic material than what is currently available to properly sort out the taxonomic status of several lineages in that clade. © 2016 Magnolia Press.


Gehara M.,TU Braunschweig | Gehara M.,Federal University of Rio Grande do Norte | Crawford A.J.,University of Los Andes, Colombia | Crawford A.J.,Smithsonian Tropical Research Institute | And 29 more authors.
PLoS ONE | Year: 2014

Species distributed across vast continental areas and across major biomes provide unique model systems for studies of biotic diversification, yet also constitute daunting financial, logistic and political challenges for data collection across such regions. The tree frog Dendropsophus minutus (Anura: Hylidae) is a nominal species, continentally distributed in South America, that may represent a complex of multiple species, each with a more limited distribution. To understand the spatial pattern of molecular diversity throughout the range of this species complex, we obtained DNA sequence data from two mitochondrial genes, cytochrome oxidase I (COI) and the 16S rhibosomal gene (16S) for 407 samples of D. minutus and closely related species distributed across eleven countries, effectively comprising the entire range of the group. We performed phylogenetic and spatially explicit phylogeographic analyses to assess the genetic structure of lineages and infer ancestral areas. We found 43 statistically supported, deep mitochondrial lineages, several of which may represent currently unrecognized distinct species. One major clade, containing 25 divergent lineages, includes samples from the type locality of D. minutus. We defined that clade as the D. minutus complex. The remaining lineages together with the D. minutus complex constitute the D. minutus species group. Historical analyses support an Amazonian origin for the D. minutus species group with a subsequent dispersal to eastern Brazil where the D. minutus complex originated. According to our dataset, a total of eight mtDNA lineages have ranges >100,000 km2. One of them occupies an area of almost one million km2 encompassing multiple biomes. Our results, at a spatial scale and resolution unprecedented for a Neotropical vertebrate, confirm that widespread amphibian species occur in lowland South America, yet at the same time a large proportion of cryptic diversity still remains to be discovered. © 2014 Gehara et al.


Fouquet A.,CNRS Guyane USR3456 | Orrico V.G.D.,University Estadual Of Santa Cruz | Ernst R.,Museum of Zoology | Blanc M.,Pointe Maripa | And 6 more authors.
Zootaxa | Year: 2015

Many Amazonian frog species that are considered widely distributed may actually represent polyspecific complexes.. A minute tree frog from the Guiana Shield originally assigned to the allegedly widely distributed Dendropsophus brevifrons proved to be a yet undescribed species within the D. parviceps group. We herein describe this new species and present a phylogeny for the D. parviceps group. The new species is diagnosed from other Dendropsophus of the parviceps group by its small body size (19.6-21.7 mm in males, 22.1-24.5 mm in females), thighs dorsally dark grey with cream blotches without bright yellow patch, absence of dorsolateral and canthal stripe, and an advertisement call comprising trills (length 0.30-0.35 s) composed of notes emitted at a rate of 131-144 notes/s, generally followed by click series of 2-3 notes. Its tadpole is also singular by having fused lateral marginal papillae and absence of both labial teeth and submarginal papillae. Genetic distances (p-distance) are >5.3% on the 12S and >9.3% on the 16S from D. brevifrons, its closest relative. This species occurs from the Brazilian state of Amapá, across French Guiana and Suriname to central Guyana and is likely to also occur in adjacent Brazilian states and eastern Venezuela. This species is not rare but is difficult to collect because of its arboreal habits and seasonal activity peaks. © 2015 Magnolia Press.


Fouquet A.,CNRS Guyane USR3456 | Fouquet A.,University of Sao Paulo | Santana Cassini C.,São Paulo State University | Fernando Baptista Haddad C.,São Paulo State University | And 2 more authors.
Journal of Biogeography | Year: 2014

Aim: For many taxa, inaccuracy of species boundaries and distributions hampers inferences about diversity and evolution. This is particularly true in the Neotropics where prevalence of cryptic species has often been demonstrated. The frog genus Adenomera is suspected to harbour many more species than the 16 currently recognized. These small terrestrial species occur in Amazonia, Atlantic Forest (AF), and in the open formations of the Dry Diagonal (DD: Chaco, Cerrado and Caatinga). This widespread and taxonomically complex taxon provides a good opportunity to (1) test species boundaries, and (2) investigate historical connectivity between Amazonia and the AF and associated patterns of diversification. Location: Tropical South America east of the Andes. Methods: We used molecular data (four loci) to estimate phylogenetic relationships among 320 Adenomera samples. These results were integrated with other lines of evidence to propose a conservative species delineation. We subsequently used an extended dataset (seven loci) and investigated ancestral area distributions, dispersal-vicariance events, and the temporal pattern of diversification within Adenomera. Results: Our conservative delineation identified 31 Confirmed Candidate Species (four remaining unconfirmed) representing a 94% increase in species richness. The biogeographical analysis suggested an Amazonian origin of Adenomera with as many as three dispersals to the DD and one to the AF during the Miocene. These dispersals were associated with habitat shifts from forest towards open habitats. Main conclusions: The DD played a major role in the history of Adenomera in limiting dispersal and favouring diversification of open-habitat lineages. Moreover, a forest bridge during the Miocene Climatic Optimum may have permitted dispersal from Amazonia towards the AF and subsequent diversification. Uncovering species boundaries and distributions might drastically change inferences based on currently perceived distribution patterns. © 2013 John Wiley & Sons Ltd.


PubMed | Pointe Maripa, Museum of Zoology, CNRS Guyane USR3456, Anton De Kom University of Suriname and 4 more.
Type: Journal Article | Journal: Zootaxa | Year: 2015

Many Amazonian frog species that are considered widely distributed may actually represent polyspecific complexes.. A minute tree frog from the Guiana Shield originally assigned to the allegedly widely distributed Dendropsophus brevifrons proved to be a yet undescribed species within the D. parviceps group. We herein describe this new species and present a phylogeny for the D. parviceps group. The new species is diagnosed from other Dendropsophus of the parviceps group by its small body size (19.6-21.7 mm in males, 22.1-24.5 mm in females), thighs dorsally dark grey with cream blotches without bright yellow patch, absence of dorsolateral and canthal stripe, and an advertisement call comprising trills (length 0.30-0.35 s) composed of notes emitted at a rate of 131-144 notes/s, generally followed by click series of 2-3 notes. Its tadpole is also singular by having fused lateral marginal papillae and absence of both labial teeth and submarginal papillae. Genetic distances (p-distance) are >5.3% on the 12S and >9.3% on the 16S from D. brevifrons, its closest relative. This species occurs from the Brazilian state of Amap, across French Guiana and Suriname to central Guyana and is likely to also occur in adjacent Brazilian states and eastern Venezuela. This species is not rare but is difficult to collect because of its arboreal habits and seasonal activity peaks.

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