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Michael Wink - One of the best experts on this subject based on the ideXlab platform.

  • mitochondrial phylogeography of the european pond turtle emys orbicularis linnaeus 1758
    Molecular Ecology, 1999
    Co-Authors: Peter Lenk, Uwe Fritz, U Joger, Michael Wink
    Abstract:

    The phylogeny and phylogeography of Emys orbicularis was inferred from mitochondrial nucleotide sequences of the cytochrome b gene analysed by DNA sequencing and RNA heteroduplex analysis. Within the family Emydidae the monotypic genus Emys is affiliated with the nearctic taxa Emydoidea blandingii and Clemmys marmorata. The analysis of 423 individuals of E. orbicularis, originating throughout its distribution range, revealed a remarkable intraspecific differentiation in 20 different haplotypes with distinct geographical ranges. Maximum parsimony analysis produced a star-like phylogeny with seven main lineages which may reflect separations in the late Pliocene. The haplotype distribution examined by partial Mantel tests and analysis of molecular variance revealed a substantial effect of glacial periods. This historical perspective suggests the existence of multiple glacial refugia and considerable Holocene range expansion which was modulated by climatic traits. Further support is gained for the occurrence of long-term parapatry in glacial refugia.

Luna, Carlos A. - One of the best experts on this subject based on the ideXlab platform.

  • Presencia de Trachemys Agassiz, 1857 (Testudines, Emydidae) en el Pleistoceno tardío del centro de la Argentina
    2011
    Co-Authors: Cabrera, Mario Roberto, Luna, Carlos A.
    Abstract:

    En este trabajo se describen restos del caparazón de una tortuga que constituyen el primer registro del género dulceacuícola Trachemys Agassiz, 1857 y de la familia Emydidae Rafinesque, 1815 en la provincia de Córdoba, y el hallazgo más occidental de ambos en la Argentina. Los materiales recuperados consisten en la placa proneural, las placas pleurales IV y VIII derechas y fragmentos de las placas pleurales III y IV izquierdas, epiplastron, hioplastron e hipoplastron derechos, más tres fragmentos indeterminables. Los restos provienen del Sitio El Silencio (30°53'20" S, 62°49'29" W), un yacimiento paleontológico de edad Pleistoceno tardío - Holoceno temprano, expuesto en la costa de la actual laguna Mar Chiquita, en un nivel de limo con intercalaciones de carbonato de calcio asignado a la Formación Tezanos Pinto, cuya depositación se produjo entre los 36.000 y 8.000 AP. El registro es relacionado con un evento húmedo acontecido entre los 16.500 y 15.500 años AP, que pudo haber sido lo suficientemente marcado y sostenido como para posibilitar el ingreso de Trachemys (y otros taxones vertebrados) durante el Pleistoceno a cercanías de la laguna Mar Chiquita, unos 220 km hacia el oeste de su distribución actual.The first fossil record at central Argentina of both the turtle genus Trachemys Agassiz, 1857 and the family Emydidae Rafinesque, 1815 is described. The fossil material, of late Pleistocene-early Holocene age, is composed of the proneural plate, the right pleurals IV and VIII, and fragments of the left pleurals III and IV, parts of the right epiplastron, hyoplastron and hypoplastron, and three indeterminate fragments. These shell elements were discovered at El Silencio Site (30°53'20" S, 62°49'29" W), southern coast of the saline Mar Chiquita Lake, Córdoba province, Argentina, in a siltite level with calcium carbonate intercalations assigned to the Tezanos Pinto Formation, whose deposition occurred between 36000 and 8000 years BP. The fossil record is related to a humid event between 16500 and 15500 years BP that, if marked and temporarily sustained enough, may have favoured the colonization by Trachemys (as well as other vertebrate taxa) during the Pleistocene into this area where the genus do not live today, 220 km far to the west of its present distribution.Asociación Herpetológica Argentina (AHA

  • Presencia de Trachemys Agassiz, 1857 (Testudines, Emydidae) en el Pleistoceno tardío del centro de la Argentina
    Asociación Herpetológica Argentina, 2011
    Co-Authors: Cabrera, Mario R., Luna, Carlos A.
    Abstract:

    En este trabajo se describen restos del caparazón de una tortuga que constituyen el primer registro del género dulceacuícola Trachemys Agassiz, 1857 y de la familia Emydidae Rafinesque, 1815 en la provincia de Córdoba, y el hallazgo más occidental de ambos en la Argentina. Los materiales recuperados consisten en la placa proneural, las placas pleurales IV y VIII derechas y fragmentos de las placas pleurales III y IV izquierdas, epiplastron, hioplastron e hipoplastron derechos, más tres fragmentos indeterminables. Los restos provienendel Sitio El Silencio (30°53’20" S, 62°49’29" W), un yacimiento paleontológico de edad Pleistoceno tardío - Holoceno temprano, expuesto en la costa de la actual laguna Mar Chiquita, en un nivel de limo con intercalaciones de carbonato de calcio asignado a la Formación Tezanos Pinto, cuya depositación se produjo entre los 36.000 y 8.000 AP. El registro esrelacionado con un evento húmedo acontecido entre los 16.500 y 15.500 años AP, que pudo haber sido lo suficientemente marcado y sostenido como para posibilitar el ingreso deTrachemys (y otros taxones vertebrados) durante el Pleistoceno a cercanías de la laguna Mar Chiquita, unos 220 km hacia el oeste de su distribución actual

Peter Lenk - One of the best experts on this subject based on the ideXlab platform.

  • mitochondrial phylogeography of the european pond turtle emys orbicularis linnaeus 1758
    Molecular Ecology, 1999
    Co-Authors: Peter Lenk, Uwe Fritz, U Joger, Michael Wink
    Abstract:

    The phylogeny and phylogeography of Emys orbicularis was inferred from mitochondrial nucleotide sequences of the cytochrome b gene analysed by DNA sequencing and RNA heteroduplex analysis. Within the family Emydidae the monotypic genus Emys is affiliated with the nearctic taxa Emydoidea blandingii and Clemmys marmorata. The analysis of 423 individuals of E. orbicularis, originating throughout its distribution range, revealed a remarkable intraspecific differentiation in 20 different haplotypes with distinct geographical ranges. Maximum parsimony analysis produced a star-like phylogeny with seven main lineages which may reflect separations in the late Pliocene. The haplotype distribution examined by partial Mantel tests and analysis of molecular variance revealed a substantial effect of glacial periods. This historical perspective suggests the existence of multiple glacial refugia and considerable Holocene range expansion which was modulated by climatic traits. Further support is gained for the occurrence of long-term parapatry in glacial refugia.

Marcelo S. De La ,fuente - One of the best experts on this subject based on the ideXlab platform.

Uwe Fritz - One of the best experts on this subject based on the ideXlab platform.

  • molecular phylogeny of central and south american slider turtles implications for biogeography and systematics testudines Emydidae trachemys
    Journal of Zoological Systematics and Evolutionary Research, 2012
    Co-Authors: Uwe Fritz, Heiko Stuckas, Mario Vargasramirez, Anna K Hundsdorfer, Jerome Maran, Martin Packert
    Abstract:

    We analyse phylogeny, systematics and biogeography of slider turtles (Trachemys spp.) using sequence data of four mitochondrial genes (3242 bp) and five nuclear loci (3396 bp) of most South American and southern Central American taxa and representatives of northern Central American, West Indian and North American slider species (16 species and subspecies) and allied North American species (genera Chrysemys, Deirochelys, Graptemys, Malaclemys, Pseudemys). By applying maximum likelihood, relaxed molecular clock and ancestral range analyses, we provide evidence for two successive colonizations of South America by slider turtles. In addition, we show that the current species delineation of Central and South American slider turtles is incorrect. Our data suggest that Trachemys grayi is a distinct polytypic species that embraces, besides the nominotypical subspecies, T. g. emolli and T. g. panamensis. Trachemys ornata is also polytypic with the subspecies T. o. ornata, T. o. callirostris, T. o. cataspila, T. o. chichiriviche and T. o. venusta. Moreover, T. adiutrix should be regarded as a subspecies of T. dorbigni. All studied Trachemys species are inferred to have originated in the Late Miocene to Early Pliocene. The ancestor of the two subspecies of T. dorbigni colonized South America most probably prior to the establishment of the land bridge connecting Central and South America, whereas the two South American subspecies of T. ornata represent a younger independent immigration wave from Central America.

  • mitochondrial phylogeography of the european pond turtle emys orbicularis linnaeus 1758
    Molecular Ecology, 1999
    Co-Authors: Peter Lenk, Uwe Fritz, U Joger, Michael Wink
    Abstract:

    The phylogeny and phylogeography of Emys orbicularis was inferred from mitochondrial nucleotide sequences of the cytochrome b gene analysed by DNA sequencing and RNA heteroduplex analysis. Within the family Emydidae the monotypic genus Emys is affiliated with the nearctic taxa Emydoidea blandingii and Clemmys marmorata. The analysis of 423 individuals of E. orbicularis, originating throughout its distribution range, revealed a remarkable intraspecific differentiation in 20 different haplotypes with distinct geographical ranges. Maximum parsimony analysis produced a star-like phylogeny with seven main lineages which may reflect separations in the late Pliocene. The haplotype distribution examined by partial Mantel tests and analysis of molecular variance revealed a substantial effect of glacial periods. This historical perspective suggests the existence of multiple glacial refugia and considerable Holocene range expansion which was modulated by climatic traits. Further support is gained for the occurrence of long-term parapatry in glacial refugia.