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Richard C Vogt - One of the best experts on this subject based on the ideXlab platform.
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Diet of an Assemblage of Four Species of Turtles (Podocnemis) in the Rio Uatumã, Amazonas, Brazil
Copeia, 2020Co-Authors: Fernando L. R. Cunha, Rafael Bernhard, Richard C VogtAbstract:The structure and functioning of freshwater turtle communities remain understudied topics, especially in tropical regions where biodiversity is higher. The objective of our study was to compare the diets of Podocnemis erythrocephala ,P. expansa, P. sextuberculata, and P. unifilis living in syntopy in Amazonas, Brazil. We tested for qualitative and quantitative variations in the way different species used the same available food resources. We collected fresh stomach flushings from all turtles captured in trammel nets in three lakes in 2012. Sampling was conducted in the four distinct tropical seasons: beginning of rainy season (rising water), peak of rainy season (rapidly rising water), end of rainy season (highest flooded forest water level), and dry season (when water levels were receding). We tested the hypothesis that different food items are available in different quantities at different times of the year due to the seasonality of fruiting trees and other plants in response to the wet and dry conditions. We examined whether food items consumed were related to turtle body size and if there was feeding niche overlap among species. Podocnemis sextuberculata consumed the least amount of food by volume, while P. expansa consumed the highest diversity of food items. All four species are primarily herbivorous, and their diets were composed mainly of fruits and seeds (85.4% mean proportion by volume). Genipa americana (Rubiaceae) was most important in the diet of all species, except in P. sextuberculata. We found some evidence of seasonal differences in the consumption of some plant species. Body size did not influence qualitative (diversity of food items eaten) or quantitative variation of food items (volume), except in P. erythrocephala for which we detected a significant linear relationship between carapace length and the volume of stomach contents. The highest food niche overlap was between P. expansa and P. unifilis, and the lowest niche overlap was between P. erythrocephala and P. sextuberculata. Turtles tended to partition food resources more in areas that had more species feeding in syntopy than in areas with fewer syntopic species.
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Home Range of Yellow-spotted Amazon River Turtles (Podocnemis unifilis) (testudines: Podocnemididae) in the Trombetas River Biological Reserve, Pará, Brazil
Chelonian Conservation and Biology, 2019Co-Authors: Sofia Ponce De Leão, Shirley Famelli, Richard C VogtAbstract:Abstract Adult Podocnemis unifilis were monitored using VHF radio tracking from September 2013 to September 2014 in the Rio Trombetas Biological Reserve, Para, Brazil. Our aim was to analyze the us...
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Vulnerability of Giant South American Turtle (Podocnemis expansa) nesting habitat to climate-change-induced alterations to fluvial cycles:
Tropical Conservation Science, 2016Co-Authors: Carla C Eisemberg, Virginia Campos Diniz Bernardes, Shirley Famelli, Rafael Antônio Machado Balestra, Fernanda Freda Pereira, Richard C VogtAbstract:A change in seasonal flooding cycles in the Amazon may negatively impact nesting success of the Giant South American Turtle (Podocnemis expansa). Our aim was to devise a technique that could be rep...
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testing the effects of barriers on the genetic connectivity in Podocnemis erythrocephala red headed amazon river turtle implications for management and conservation
Chelonian Conservation and Biology, 2016Co-Authors: Rafaela Cardoso Dos Santos, Richard C Vogt, Maria Das Neves Silva Viana, Luiz Alberto Dos Santos Monjeló, Paulo César Machado Andrade, Paulo Henrique Guimarães Oliveira, Juarez Carlos Brito Pezzuti, Jack W. Sites, Jackson Pantojalima, Tomas HrbekAbstract:Abstract In contrast to the other Podocnemis species, Podocnemis erythrocephala (Pleurodira: Podocnemididae) is restricted to blackwater and clearwater rivers and lakes, including the Negro River basin, and several other tributaries of the eastern Amazon River basin. In order to test the effects of geographic barriers on genetic connectivity of P. erythrocephala, 10 localities sampled throughout the Brazilian Amazon basin were studied. Two hundred and forty-six specimens were sequenced for the mitochondrial control region. Analysis of molecular variance confirmed the existence of population subdivision (ΦST = 0.28, p < 0.001). In pairwise comparisons, the values of the fixation index ΦST were significant in almost all comparisons involving the Sao Gabriel da Cachoeira (Negro River), Jau National Park (Jau River), and Barreirinha (Andira River), indicating that these populations are genetically differentiated. Genetic differentiation is most likely explained by the presence of rapids and waterfalls separat...
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relationship between multiple paternity and reproductive parameters for Podocnemis sextuberculata testudines podocnemididae in the trombetas river brazil
Genetics and Molecular Research, 2016Co-Authors: F P Freda, Virginia Campos Diniz Bernardes, Carla C Eisemberg, C Fantin, Richard C VogtAbstract:: Genetic studies of multiple paternity are a valuable tool to gain information on the reproductive biology of turtles. We analyzed paternity type in Podocnemis sextuberculata and related number of fathers per nest to nesting period (beginning, middle, or end of nesting season); clutch size (number of eggs); female size; and hatchling success. Females were captured and maximum linear carapace lengths measured during the 60 days that encompass the nesting season at Rio Trombetas Biological Reserve (Para, Brazil). Nests were marked and blood samples collected from hatchlings. Six heterologous loci were used: five from Podocnemis unifilis and one from Podocnemis expansa. Hatchlings were analyzed from 23 nests, and the rate of multiple paternity was 100%. The mean number of fathers per nest was six (± 0.9), and no significant difference between number of fathers in a nest and nesting period. Similarly there was no significant relationship between number of fathers in a nest and female size or hatchling success rate. Number of fathers was, however, positively correlated with clutch size (Spearman correlation rho = 0.47; P > 0.05). To our knowledge, this is the first study to test the relationship between multiple paternity and ecological aspects of the reproductive ecology of turtles in the genus Podocnemis.
Izeni Pires Farias - One of the best experts on this subject based on the ideXlab platform.
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Model-based riverscape genetics: disentangling the roles of local and connectivity factors in shaping spatial genetic patterns of two Amazonian turtles with different dispersal abilities
Evolutionary Ecology, 2019Co-Authors: Jessica Dos Anjos Oliveira, Izeni Pires Farias, Gabriel C. Costa, Fernanda P. WerneckAbstract:Genetic patterns are shaped by the interaction of different factors such as distance, barriers, landscape resistance and local environment. The relative importance of these processes may vary for species with different ecological traits. Here we compared two related Amazonian riverine turtle species ( Podocnemis erythrocephala and Podocnemis sextuberculata ) with distinct dispersal abilities to assess how differently local and connectivity variables influence their genetic patterns. We used a total of 609 genetic samples to estimate mitochondrial (mtDNA) genetic diversity and differentiation for each locality. We applied model selection on models associating genetic diversity to local variables representing hypotheses of climate and primary productivity, water level variation, hunting pressure and downstream increase in genetic diversity. We modeled the relationship of genetic differentiation with connectivity variables representing hypotheses of isolation by distance (IBD), isolation by resistance (IBR) and isolation by barrier (IBB). Model selection for genetic diversity was only important (excluded the null model) for the high-dispersal species ( P. sextuberculata ), with best models including hypotheses of productivity and hunting pressure. Genetic diversity was higher in more productive sites and in sites with higher concentration of villages (opposed to expected). Although a variable importance testing showed low importance for connectivity models, IBB (Amazon River) and IBR (resistance by current and past climatic suitability and river color) models explained more genetic differentiation turnover than IBD (riverway distance). Models explained a higher percentage of genetic differentiation for the low-dispersal species ( P. erythrocephala ), with Amazon River as main predictor. We show that, although local variables are often overlooked in riverscape genetics studies, they can influence intrapopulacional genetic diversity of aquatic species, even those with high dispersal ability. By applying a resistance-model framework and by using riverscape genetics factors relevant in basin-wide context, we provide a novel approach to investigate genetic patterns of other aquatic vertebrates in fluvial systems.
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Polyandrous behavior in an overexploited giant South American turtle (Podocnemis expansa) population in Central Amazon, Brazil.
Genetics and Molecular Research, 2017Co-Authors: Cleiton Fantin, J. Morais, R. Botero-arias, C. Araújo, C. Camillo, Izeni Pires FariasAbstract:The aim of the present study was to investigate the reproductive behavior of the giant Amazon River turtle (Podocnemis expansa) in the Amazon. This was carried out by estimating the degree of polymorphism in five DNA microsatellites in a sample of 359 hatchlings from 12 nests in the Mamiraua Sustainable Development Reserve in the municipality of Tefe, state of Amazonas, Brazil. An analysis of allele frequency and variation in the five microsatellite loci allowed for determination of multiple paternity in all nests sampled. Contributions of at least four male turtles to one nest, three male turtles to six nests, and two male turtles to five nests were identified. Knowledge on the reproductive behavior of P. expansa can assist in the establishment of management and conservation strategies for the population in the Mamiraua Reserve.
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Evidence of multiple paternal contribution in Podocnemis sextuberculata (Testudines: Podocnemididae) detected by microsatellite markers
Phyllomedusa: Journal of Herpetology, 2015Co-Authors: Cleiton Fantin, Luiz Alberto Dos Santos Monjeló, Tomas Hrbek, Dorothy Ivila De Melo Pereira, Jorge Frank Braga Ferreira, Paulo Cesar Andrade Machado, Izeni Pires FariasAbstract:Evidence of multiple paternity in Podocnemis sextuberculata (Testudines: Podocnemididae) detected by microsatellite markers. We found evidence of multiple paternity in a sample of 12 Podocnemis sextuberculata nests including seven nests (80 hatchlings) collected along the Amazonas River, in the municipality of Barreirinha, AM, Brazil and five nests in the Abufari Biological Reserve, Tapaua, AM, Brazil (54 hatchlings). As observed in other species of the genus, P. sextuberculata also presented polyandric behavior. By means of allelic frequency and variation in six microsatellite loci for each location, the occurrence of multiple paternity in sampled nests of this species was inferred, even though the maternal genotype was unknown. For one of the nests, a minimum of four males contributed to the clutch, whereas for nearly all remaining nests at least two males contributed. Only one of the twelve nests did not show clear evidence for contributions from more than one male. This is the first genetic evidence of multiple paternity in P. sextuberculata
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Polyandry in the red-headed river turtle Podocnemis erythrocephala (Testudines, Podocnemididae) in the Brazilian Amazon.
Genetics and Molecular Research, 2010Co-Authors: Cleiton Fantin, Luiz Alberto Dos Santos Monjeló, Izeni Pires Farias, Tomas HrbekAbstract:The genus Podocnemis comprises six living species, including P. erythrocephala (irapuca-red-headed river turtle). Data are available concerning the reproductive biology of the species of the genus Podocnemis, but little is known about their reproductive strategies. Considering the total lack of such data for P. erythrocephala, and with the goal of contributing information on their mode of reproduction, we examined the relationships among individuals of nests of this turtle, using microsatellite markers. Using four microsatellite loci, we analyzed the progeny in six nests from two localities in the Brazilian Amazon (Santa Isabel do rio Negro and Parintins). All juveniles from each nest were analyzed. The genotypes of each juvenile from each nest were identified, and because a sample of female DNA was not available, the maternal genotype was inferred from homozygous individuals in each nest. We found that this species is promiscuous; there was multiple paternity in five of the six nests analyzed. In addition to being important for the understanding of evolutionary and genetic processes, this type of information will be useful for chelonian management projects. Our data suggest one possible difference between reproductive patterns of the different populations. This multi-paternal condition may be a natural reproductive strategy for the preservation of the genetic diversity of this species.
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microsatellite dna markers for Podocnemis unifilis the endangered yellow spotted amazon river turtle
Molecular Ecology Notes, 2007Co-Authors: Cleiton Fantin, Luiz Alberto Dos Santos Monjeló, Tomas Hrbek, Cecilia F Carvalho, W Jack J R Sites, Spartaco Astolfifilho, Izeni Pires FariasAbstract:We developed specific primers for microsatellite DNA regions of Podocnemis unifilis and tested their utility in population genetic and paternity studies on the species and other closely related Amazonian chelonians. Seventeen microsatellite loci were polymorphic in P. unifilis and all, plus two monomorphic microsatellites in P. unifilis, were polymorphic in at least one additional chelonian species, including Peltocephalus dumeriliana .
Wilfried Klein - One of the best experts on this subject based on the ideXlab platform.
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ventilation and gas exchange in two turtles Podocnemis unifilis and phrynops geoffroanus testudines pleurodira
Respiratory Physiology & Neurobiology, 2016Co-Authors: Tábata E.f. Cordeiro, Augusto Shinya Abe, Wilfried KleinAbstract:Abstract Turtles (Testudines) have two major taxa, Pleurodira and Cryptodira. To date, only limited data are available regarding the respiratory physiology of pleurodirans. To begin to address this, we studied ventilation and gas exchange in Podocnemis unifilis and Phrynops geoffroanus . Breathing pattern in both species could be described as episodic with breathing episodes separated by large non-ventilatory periods. We measured duration of inspiration and expiration, breathing frequency, duration of the non-ventilatory period (time between episodes), tidal volume, and oxygen consumption when breathing normoxia, hypoxia and hypercarbia at 25 °C. In both species hypercarbia caused a greater increase in ventilation compared to hypoxia, increasing both breathing frequency and tidal volume. Minute ventilation and oxygen consumption in P. geoffroanus were the lowest described so far in testudines, indicating either extra-pulmonary gas exchange or a significantly lower metabolism. Oxidative costs of breathing, estimated using the regression method, was the highest described so far for any reptile. Further studies are necessary to better understand respiratory physiology in Phrynops and Podocnemis species.
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Ventilation and gas exchange in two turtles: Podocnemis unifilis and Phrynops geoffroanus (Testudines: Pleurodira)☆
Respiratory Physiology & Neurobiology, 2016Co-Authors: Tábata E.f. Cordeiro, Augusto Shinya Abe, Wilfried KleinAbstract:Abstract Turtles (Testudines) have two major taxa, Pleurodira and Cryptodira. To date, only limited data are available regarding the respiratory physiology of pleurodirans. To begin to address this, we studied ventilation and gas exchange in Podocnemis unifilis and Phrynops geoffroanus . Breathing pattern in both species could be described as episodic with breathing episodes separated by large non-ventilatory periods. We measured duration of inspiration and expiration, breathing frequency, duration of the non-ventilatory period (time between episodes), tidal volume, and oxygen consumption when breathing normoxia, hypoxia and hypercarbia at 25 °C. In both species hypercarbia caused a greater increase in ventilation compared to hypoxia, increasing both breathing frequency and tidal volume. Minute ventilation and oxygen consumption in P. geoffroanus were the lowest described so far in testudines, indicating either extra-pulmonary gas exchange or a significantly lower metabolism. Oxidative costs of breathing, estimated using the regression method, was the highest described so far for any reptile. Further studies are necessary to better understand respiratory physiology in Phrynops and Podocnemis species.
Marcia Cristina Cury - One of the best experts on this subject based on the ideXlab platform.
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concomitant infection of haemogregarina sp and staphylococcus aureus in free living yellow spotted river turtle Podocnemis unifilis case report
Archives of Veterinary Science, 2018Co-Authors: Leticia Pereira Ungari, Andre Luiz Quagliatto Santos, Guilherme Carrara Moreira Paiva, Kelem Cristina Pereira Mota, Lizandra Ferreira De Almeida Borges, Marcia Cristina CuryAbstract:A male adult yellow-spotted river turtle Podocnemis unifilis (Chordata: Testudines: Podocnemididae) was captured during field collections. Blood sample was collected for haemoparasite screening by conventional light microscopy. Morphometric and morphological analyzes of the parasite developmental stages were performed in the blood extensions, as well as the parasitemia intensity. Gametocytes of hemogregarines and innumerable bacterial cells were observed. To identify the bacteria present, a culture was performed and the presence of Staphylococcus aureus was observed. It was concluded that a co-infection of Staphylococcus aureus (Firmicutes: Bacillales: Staphylococcaceae) and Haemogregarina sp. (Apicomplexa: Adeleina: Haemogregarinidae) was observed in this free-living yellow-spotted river turtle Podocnemis unifilis.
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Haemogregarina Podocnemis sp. nov.: description of a new species of Haemogregarina Danilewsky 1885 (Adeleina: Haemogregarinaidae) in free-living and captive yellow-spotted river turtles Podocnemis unifilis (Testudines: Podocnemididae) from Brazil
Parasitology Research, 2018Co-Authors: Leticia Pereira Ungari, Andre Luiz Quagliatto Santos, Guilherme Carrara Moreira Paiva, Lucia Helena O’dwyer, Maria Regina Lucas Silva, Natália Nasser Melo Fava, Rogério Melo Costa Pinto, Marcia Cristina CuryAbstract:Based on morphological, morphometric, and molecular data, we describe a new hemoparasite of the genus Haemogregarina Danilewsky 1885, isolated from the Brazilian aquatic turtle Podocnemis unifilis (Testudines: Podocnemididae). The new species, Haemogregarina Podocnemis sp. nov. (Apicomplexa: Haemogregarinidae), is characterized by small trophozoites with a single cytoplasmic vacuole on one side; pre-meronts with nuclear chromatin dispersed in the cytoplasm, with or without cytoplasmic vacuoles; meronts that are usually broad and slightly curved (kidney-shaped), with an average of eight small rectangular nuclei; immature gamonts (bean-shaped) with two morphological types: one with nuclear chromatin dispersed in the cytoplasm and the other with nuclei in the middle of the cell; mature gamonts of two morphological types: one with a length equal to or greater than that of the erythrocyte and the width of the nuclei similar to that of the hemoparasite and the other smaller than the erythrocyte with the width of the nuclei less than that of the hemoparasite. This is the first hemogregarine species described that infects the Brazilian turtle Po. unifilis . These findings highlight the need for further studies of Haemogregarina spp. to better determine the biodiversity of this understudied parasite group.
Tomas Hrbek - One of the best experts on this subject based on the ideXlab platform.
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testing the effects of barriers on the genetic connectivity in Podocnemis erythrocephala red headed amazon river turtle implications for management and conservation
Chelonian Conservation and Biology, 2016Co-Authors: Rafaela Cardoso Dos Santos, Richard C Vogt, Maria Das Neves Silva Viana, Luiz Alberto Dos Santos Monjeló, Paulo César Machado Andrade, Paulo Henrique Guimarães Oliveira, Juarez Carlos Brito Pezzuti, Jack W. Sites, Jackson Pantojalima, Tomas HrbekAbstract:Abstract In contrast to the other Podocnemis species, Podocnemis erythrocephala (Pleurodira: Podocnemididae) is restricted to blackwater and clearwater rivers and lakes, including the Negro River basin, and several other tributaries of the eastern Amazon River basin. In order to test the effects of geographic barriers on genetic connectivity of P. erythrocephala, 10 localities sampled throughout the Brazilian Amazon basin were studied. Two hundred and forty-six specimens were sequenced for the mitochondrial control region. Analysis of molecular variance confirmed the existence of population subdivision (ΦST = 0.28, p < 0.001). In pairwise comparisons, the values of the fixation index ΦST were significant in almost all comparisons involving the Sao Gabriel da Cachoeira (Negro River), Jau National Park (Jau River), and Barreirinha (Andira River), indicating that these populations are genetically differentiated. Genetic differentiation is most likely explained by the presence of rapids and waterfalls separat...
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Testing the Effects of Barriers on the Genetic Connectivity in Podocnemis erythrocephala (Red-Headed Amazon River Turtle): Implications for Management and Conservation
Chelonian Conservation and Biology, 2016Co-Authors: Rafaela Cardoso Dos Santos, Richard C Vogt, Maria Das Neves Silva Viana, Luiz Alberto Dos Santos Monjeló, Paulo César Machado Andrade, Jackson Pantoja-lima, Paulo Henrique Guimarães Oliveira, Juarez Carlos Brito Pezzuti, Jack W. Sites, Tomas HrbekAbstract:Abstract In contrast to the other Podocnemis species, Podocnemis erythrocephala (Pleurodira: Podocnemididae) is restricted to blackwater and clearwater rivers and lakes, including the Negro River basin, and several other tributaries of the eastern Amazon River basin. In order to test the effects of geographic barriers on genetic connectivity of P. erythrocephala, 10 localities sampled throughout the Brazilian Amazon basin were studied. Two hundred and forty-six specimens were sequenced for the mitochondrial control region. Analysis of molecular variance confirmed the existence of population subdivision (ΦST = 0.28, p
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Evidence of multiple paternal contribution in Podocnemis sextuberculata (Testudines: Podocnemididae) detected by microsatellite markers
Phyllomedusa: Journal of Herpetology, 2015Co-Authors: Cleiton Fantin, Luiz Alberto Dos Santos Monjeló, Tomas Hrbek, Dorothy Ivila De Melo Pereira, Jorge Frank Braga Ferreira, Paulo Cesar Andrade Machado, Izeni Pires FariasAbstract:Evidence of multiple paternity in Podocnemis sextuberculata (Testudines: Podocnemididae) detected by microsatellite markers. We found evidence of multiple paternity in a sample of 12 Podocnemis sextuberculata nests including seven nests (80 hatchlings) collected along the Amazonas River, in the municipality of Barreirinha, AM, Brazil and five nests in the Abufari Biological Reserve, Tapaua, AM, Brazil (54 hatchlings). As observed in other species of the genus, P. sextuberculata also presented polyandric behavior. By means of allelic frequency and variation in six microsatellite loci for each location, the occurrence of multiple paternity in sampled nests of this species was inferred, even though the maternal genotype was unknown. For one of the nests, a minimum of four males contributed to the clutch, whereas for nearly all remaining nests at least two males contributed. Only one of the twelve nests did not show clear evidence for contributions from more than one male. This is the first genetic evidence of multiple paternity in P. sextuberculata
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Polyandry in the red-headed river turtle Podocnemis erythrocephala (Testudines, Podocnemididae) in the Brazilian Amazon.
Genetics and Molecular Research, 2010Co-Authors: Cleiton Fantin, Luiz Alberto Dos Santos Monjeló, Izeni Pires Farias, Tomas HrbekAbstract:The genus Podocnemis comprises six living species, including P. erythrocephala (irapuca-red-headed river turtle). Data are available concerning the reproductive biology of the species of the genus Podocnemis, but little is known about their reproductive strategies. Considering the total lack of such data for P. erythrocephala, and with the goal of contributing information on their mode of reproduction, we examined the relationships among individuals of nests of this turtle, using microsatellite markers. Using four microsatellite loci, we analyzed the progeny in six nests from two localities in the Brazilian Amazon (Santa Isabel do rio Negro and Parintins). All juveniles from each nest were analyzed. The genotypes of each juvenile from each nest were identified, and because a sample of female DNA was not available, the maternal genotype was inferred from homozygous individuals in each nest. We found that this species is promiscuous; there was multiple paternity in five of the six nests analyzed. In addition to being important for the understanding of evolutionary and genetic processes, this type of information will be useful for chelonian management projects. Our data suggest one possible difference between reproductive patterns of the different populations. This multi-paternal condition may be a natural reproductive strategy for the preservation of the genetic diversity of this species.
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microsatellite dna markers for Podocnemis unifilis the endangered yellow spotted amazon river turtle
Molecular Ecology Notes, 2007Co-Authors: Cleiton Fantin, Luiz Alberto Dos Santos Monjeló, Tomas Hrbek, Cecilia F Carvalho, W Jack J R Sites, Spartaco Astolfifilho, Izeni Pires FariasAbstract:We developed specific primers for microsatellite DNA regions of Podocnemis unifilis and tested their utility in population genetic and paternity studies on the species and other closely related Amazonian chelonians. Seventeen microsatellite loci were polymorphic in P. unifilis and all, plus two monomorphic microsatellites in P. unifilis, were polymorphic in at least one additional chelonian species, including Peltocephalus dumeriliana .