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The mixosaurid ichthyosaur Phalarodon cf. P. fraasi from the Middle Triassic of Guizhou Province, China

Published online by Cambridge University Press:  14 July 2015

Da-Yong Jiang
Affiliation:
Department of Geology and Geological Museum, Peking University, Beijing 100871, P. R. China
Lars Schmitz
Affiliation:
Department of Geology, University of California, Davis, 95616, USA
Ryosuke Motani
Affiliation:
Department of Geology, University of California, Davis, 95616, USA
Wei-Cheng Hao
Affiliation:
Department of Geology and Geological Museum, Peking University, Beijing 100871, P. R. China
Yuan-Lin Sun
Affiliation:
Department of Geology and Geological Museum, Peking University, Beijing 100871, P. R. China

Extract

The family Mixosauridae Baur, 1887 is a dominant group of Middle Triassic ichthyosaurs. Its generic composition has been controversial, but recent findings from southern China enabled Jiang et al. (2006) to recognize two monophyletic taxa within the clade, suggesting the presence of two genera within the family, namely Mixosaurus Baur, 1887 and Phalarodon Merriam, 1910. The latter genus, which was invalidated at one point (Nicholls et al., 1999; McGowan and Motani, 2003), was recently resurrected by Schmitz (2005) by validating its type species. Mixosaurus is Tethyan in distribution, whereas Phalarodon had been known mostly from North America and Spitsbergen, apart from a possible juvenile from Switzerland (Brinkmann, 1997, 1998). More recently, Jiang et al. (2003) reported a largely complete, yet poorly preserved skeleton as the first record of the genus Phalarodon from Asia and referred it to Phalarodon sp. However, important synapomorphies were not clearly identified, and evidence has since emerged that the specimen had been tampered with by farmers after it was collected. In the light of the cladistic analysis by Jiang et al. (2006), the referral of the specimen to the genus Phalarodon is questionable.

Type
Paleontological Notes
Copyright
Copyright © The Paleontological Society 

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