Literaturdatenbank
Literaturdatenbank |
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Vargas-Ramírez, M., Castaño-Mora, O. V., & Fritz, U. (2008). Molecular phylogeny and divergence times of ancient south american and malagasy river turtles (testudines: pleurodira: podocnemididae). Organisms Diversity & Evolution, 8(5), 388–398.
Added by: Admin (01 Feb 2009 18:31:08 UTC) Last edited by: Beate Pfau (30 May 2009 17:21:31 UTC) |
| Resource type: Journal Article DOI: 10.1016/j.ode.2008.10.001 BibTeX citation key: VargasRamirez2008a View all bibliographic details  |
Categories: General Keywords: Erymnochelys, Erymnochelys madagascariensis, Genetik = genetics, Peltocephalus, Peltocephalus dumerilianus, Podocnemididae, Podocnemis, Podocnemis erythrocephala, Podocnemis expansa, Podocnemis lewyana, Podocnemis sextuberculata, Podocnemis unifilis, Podocnemis vogli, Schildkröten = turtles + tortoises, Systematik = taxonomy Creators: Castaño-Mora, Fritz, Vargas-Ramírez Collection: Organisms Diversity & Evolution |
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| Abstract |
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Podocnemididae The eight extant podocnemidid species are the last survivors of a speciose ancient group of turtles known to have existed since the Cretaceous. One species, representing the monotypic genus Erymnochelys, occurs on Madagascar; the remaining seven species are confined to South America (Peltocephalus: one species; Podocnemis: six species). Phylogenetic relationships of all extant species were reconstructed from six mitochondrial (3385 bp) and six nuclear DNA fragments (4115 bp) in separate and combined analyses (Bayesian inference, Maximum Likelihood, Maximum Parsimony). In a total evidence approach for all concatenated genes, all methods yielded the same well-supported phylogenetic hypothesis for the three basal lineages. The Malagasy genus Erymnochelys is sister to the South American Podocnemis, and Peltocephalus constitutes the sister taxon to Erymnochelys+Podocnemis. Within Podocnemis, P. unifilis+(P. erythrocephala+P. lewyana) constitute a well-supported crown clade; P. sextuberculata, P. vogli, and P. expansa were revealed as successive sister taxa. According to Bayesian relaxed molecular clock calculations calibrated with fossil evidence, Peltocephalus originated during a period of the Late Cretaceous (not, vert, similar86 mya), when a contiguous Gondwana landmass exclusive of Africa is likely to have still existed. The Late Cretaceous split between Erymnochelys and Podocnemis (not, vert, similar78 mya) coincides with the supposed submergence of the land bridge between Madagascar and Antarctica+South America, suggesting that the origin of those genera is linked to this vicariant event. The extant Podocnemis species evolved from the Late Eocene (not, vert, similar37 mya) to the Middle Miocene (not, vert, similar15 mya), during a phase characterized by dramatic global cooling, aridification, and massive Andean uplift.
Added by: Admin Last edited by: Beate Pfau |