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The Triassic U–Pb age for the aquatic long-necked protorosaur of Guizhou, China

  • YANBIN WANG (a1) (a2), DETING YANG (a1) (a2), JUAN HAN (a3), LITING WANG (a4), JIANXIN YAO (a1) and DUNYI LIU (a1) (a2)...
Abstract

The ancient marine limestone beds of the upper part of the Guanling Formation, Panxian County, Guizhou Province, SW China, yielded a wide range of high-diversity well-preserved marine reptiles such as the fully aquatic protorosaur with an extremely long neck Dinocephalosaurus orientalis, the oldest mixosaurid ichthyosaurs and lariosaurs. However, there is no precise isotopic age to study the intriguing origin, evolution and emigration history of the important fauna. We report a sensitive high-resolution ion microprobe (SHRIMP) U–Pb zircon age for a volcanic tuff bed within the upper part of the Guanling Formation. The result indicates that the age of the fossil horizon is 244.0±1.3 Ma, 14 Ma earlier than the previously estimated age based on conodont evidence. We consider that the marine reptiles had a relatively rapid evolution during Middle Triassic time, some 8 Ma after the end-Permian mass extinction.

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Corresponding author
Author for correspondence: wangyanbin@bjshrimp.cn
References
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Benton, M. J. 2005. When Life Nearly Died: The Greatest Mass Extinction of All Time. London: Thames & Hudson. ISBN 0-500-28573-X.
Black, L. P., Kamo, S. L., Allen, C. M., Aleinikoff, J. N., Davis, D. W., Korsch, R. J. & Foudoulis, C. 2003. TEMORA 1: a new zircon standard for Phanerozoic U-Pb geochronology. Chemical Geology 200, 155–70.
Bowring, S. A., Ewrin, D. H., Jin, Y. G., Martin, M. W., Davidek, K. & Wang, W. 1998. U/Pb Zircon geochronology and tempo of the end-permian mass extinction. Science 280, 1039–45.
Bürgin, T., Rieppel, O., Sander, P. M. & Tschanz, K. 1989. The fossils of Monte San Giorgio. Scientific American 260, 6481.
Claoué-Long, J. C., Compston, W., Roberts, J. & Fanning, C. M. 1995. Two carboniferous ages: a comparison of SHRIMP zircon dating with conventional zircon ages and 40Ar/39Ar analysis. In Geochronology, Time Scales and Global Stratigraphic Correlation (eds Berggren, W. A., Kent, D.V., Aubry, M. P. & Hardenbol, J.), SEPM (Society for Sedimentary Geology) 4, 321.
Ewrin, D. H. 1993. The Great Paleozoic Crisis. New York: Cambridge University Press.
Ewrin, D. H. 1994. The Permo-Triassic extinction. Nature 367, 231–6.
Hao, W. C., Sun, Y. L., Jiang, D. Y. & Sun, Z. Y. 2006. Advance in studies of the panxian fauna. Acta Scientiarum Naturalium Universitatis Pekinensis 42, 817–23 (in Chinese with English abstract).
Jiang, D. Y., Maisch, M. W., Hao, W. C., Sun, Y. L. & Sun, Z. Y. 2006 a. A new species of Lariosaurus (Reptilia, Sauropterygia) from the Middle Anisian (Middle Triassic) of Guizhou, southwestern China. Neues Jahrbuch für Geologie und Palaöntologie Monatshefte-Abhandlungen 242, 1942.
Jiang, D. Y., Maisch, M. W., Hao, W. C., Sun, Y. L. & Sun, Z. Y. 2006 b. Nothosaurus yangjuanensis n. sp. (Reptilia, Sauropterygia, Notho-sauridae) from the middle Anisian (Middle Triassic) of Guizhou. Neues Jahrbuch für Geologie und Palaöntologie Monatshefte 2006, 257–76.
Jiang, D. Y., Motani, R., Li, C., Hao, W. C., Sun, Y. L., Sun, Z. Y. & Schmitz, L. 2005. Guanling biota: a marker of triassic biotic recovery from the end-permian extinction in the ancient guizhou sea. Acta Geologica Sinica 79, 729–38.
Jiang, D. Y., Motani, R., Hao, W. C., Rieppel, O., Sun, Y. L., Schmitz, L. & Sun, Z. Y. 2008 a. First record of placodontoidea (Reptilia, Sauropterygia, Placodontia) from the eastern Tethys. Journal of Vertebrate Paleontology 28, 904–8.
Jiang, D. Y., Rieppel, O., Motani, R., Hao, W. C., Sun, Y. L., Schmitz, L. & Sun, Z. Y. 2008 b. A new middle Triassic Eosauropterygian (Reptilia, Sauropterygia) from southwestern China. Journal of Vertebrate Paleontology 28, 1055–62.
Jiang, D. Y., Schmitz, L., Hao, W. C. & Sun, Y. L. 2006 c. A new mixosaurid ichthyosaur from the Middle Triassic of China. Journal of Vertebrate Paleontology 26, 6069.
Jiang, D. Y., Schmitz, L., Motani, R., Hao, W. C. & Sun, Y. L. 2007. The mixosaurid ichthyosaur Phalarodon cf. p. fraasi from the middle triassic of guizhou province, China. Journal of Paleontology 81, 602–5.
Li, C. 2003. First Record of Protorosaurid Reptile (Order Protorosauria) from the Middle Triassic of China. Acta Geologica Sinica 77, 419–23.
Li, C., Rieppel, O. & Labarbera, M. C. 2004. A Triassic aquatic protorosaur with an extremely long neck. Science 305, 1931.
Li, C., Wu, X. C., Cheng, Y. N., Sato, T. & Wang, L. T. 2006. An unusual archosaurian from the marine Triassic of China. Naturwissenschaften 93, 200–6.
Ludwig, K. R. 2003. Isoplot 3.00. A Geochronological Toolkit for Microsoft Excel. Berkley Geochronological Centre, Special Publication no. 4.
Motani, R., Jiang, D. Y., Tintori, A., Sun, Y. L., Hao, W. C., Boyd, A., Frlog, S. H., Schmitz, L., Shin, J.Y. & Sun, Z. Y. 2008. Horizons and assemblages of middle Triassic marine reptiles from Panxian, Guizhou, China. Journal of Vertebrate Paleontology 28, 900–3.
Mundil, R., Ludwig, K. R., Metcalfe, I. & Renne, P. R. 2004. Age and timing of the Permian Mass Extinctions: U/Pb dating of closed-system zircons. Science 305, 1760–3.
Payne, J. L., Lehrmann, D. J., Wei, J. Y., Orchard, M. J., Schrag, D. P. & Knoll, A. H. 2004. Large perturbations of the carbon cycle during recovery from the end-Permian extinction. Science 305, 506–9.
Rieppel, O. 1999. Phylogeny and paleobiogeography of Triassic Sauropterygia: problems solved and unresolved. Palaeogeography, Palaeoclimatology, Palaeoecology 153, 115.
Sahney, S. & Benton, M. J. 2008. Recovery from the most profound mass extinction of all time. Proceedings of the Royal Society: Biological 275, 759–65.
Sander, P. M. 1989. The pachypleurosaurids (Reptilia: Nothosauria) from the Middle Triassic of Monte san Giorgio (Switzerland), with the description of a new species. Philosophical Transactions of the Royal Society of London, Series B 325, 561670.
Stockar, R., Baumgartner, P. O. & Condon, D. 2012. Integrated Ladinian bio-chronostratigraphy and geochrononology of Monte San Giorgio (Southern Alps, Switzerland). Swiss Journal of Geoscience 105, 85108.
Sun, Z. Y., Hao, W. C. & Jiang, D. Y. 2003. Conodont stratigraphic evidence for the age of the Guanling fauna, Guizhou Province, China. Acta Scientiarum Naturalium Universitatis Pekinensis 39, 118–25 (in Chinese with English abstract).
Sun, Z. Y., Sun, Y. L., Hao, W. C. & Jiang, D. Y. 2006. Conodont evidence for the age of the Panxian Fauna, Guizhou, China. Acta Geologica Sinica 80, 621–30.
Wang, X. F., Bachmann, G. H., Hagdorn, H., Sander, P. M., Chen, L. D., Cheng, L., Meng, F. S. & Xu, G. H. 2008. The late Triassic black shales of the Guanling area, Guizhou Province, southwestern China: a unique marine reptile and pelagic crinoid fossil lagerstätte. Palaeontology 51, 2761.
Williams, I. S. 1998. U-Th-Pb Geochronology by Ion Microprobe. In Applications of microanalytical techniques to understanding mineralizing processes (eds McKibben, M. A., Shanks, W. C. & Ridley, W. L.). Reviews in Economic Geology 7, 135.
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Geological Magazine
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