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Oviedo, FL, United States

Le M.,New York University | Duong H.T.,Hanoi University of Science | Dinh L.D.,Hanoi University of Science | Nguyen T.Q.,Vietnam Academy of Science and Technology | And 2 more authors.
Organisms Diversity and Evolution | Year: 2014

Several important aspects of the evolution of the softshell turtle (family Trionychidae) have not been addressed thoroughly in previous studies, including the pattern and timing of diversification of major clades and species boundaries of the critically endangered Shanghai Softshell Turtle, Rafetus swinhoei. To address these issues, we analyzed data from two mitochondrial loci (cytochrome b and ND4) and one nuclear intron (R35) for all species of trionychid turtles, except Pelochelys signifera, and for all known populations of Rafetus swinhoei in Vietnam and one from China. Phylogenetic analyses using three methods (maximum parsimony, maximum likelihood, and Bayesian inference) produce a well resolved and strongly supported phylogeny. The results of our time-calibration and biogeographic optimization analyses show that trionychid dispersals out of Asia took place between 45 and 49 million years ago in the Eocene. Interestingly, the accelerated rates of diversification and dispersal within the family correspond surprisingly well to global warming periods between the mid Paleocene and the early Oligocene and from the end of the Oligocene to the mid Miocene. Our study also indicates that there is no significant genetic divergence among monophyletic populations of Rafetus swinhoei, and that previous taxonomic revision of this species is unwarranted. © 2014 Gesellschaft für Biologische Systematik. Source

Caillouet Jr. C.W.,119 Victoria Drive West | Shaver D.J.,National Park Service | Landry Jr. A.M.,Texas A&M University at Galveston | Owens D.W.,College of Charleston | Pritchard P.C.H.,Chelonian Research Institute
Chelonian Conservation and Biology | Year: 2011

Kemp's ridley sea turtle (Lepidochelys kempii) age at first nesting is the age at which an individual female successfully nests for the first time. This commentary recommends determination of the statistical distribution of age at first nesting, estimation of central tendency, and variability of age at first nesting, and application of these estimates in future age-based and life stagebased demographic modeling, as substitutes for parameter estimates based on age at sexual maturity or age at first reproduction. We hope that our commentary will encourage discussion and research on age at first nesting and its application to demographic modeling of the Kemp's ridley population. © 2011 Chelonian Research Foundation. Source

Rivas G.A.,University of Zulia | Barros T.R.,University of Zulia | Molina F.D.B.,University of Sao Paulo | Molina F.D.B.,University of Santo Amaro | And 2 more authors.
Chelonian Conservation and Biology | Year: 2015

Among the freshwater turtles recorded in Venezuela, 2 of the most enigmatic species for their scarcity and misleading distributional information are Mesoclemmys raniceps and Mesoclemmys nasuta. Based on the literature, only 3 records pertaining to these 2 species could confirm that they occur in Venezuela; however, a detailed study of the evidence demonstrates that the type of Hydraspis maculata (a synonym of M. raniceps), was not specifically collected in Venezuela and the other 2 records were an adult female of Mesoclemmys zuliae and a juvenile Mesoclemmys heliostemma. Our conclusion is that no records of M. nasuta or M. raniceps are known from Venezuela. © 2015 Chelonian Research Foundation. Source

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