An Early Cretaceous Tribosphenic Mammal and Metatherian Evolution

  title={An Early Cretaceous Tribosphenic Mammal and Metatherian Evolution},
  author={Zhe‐Xi Luo and Qiang Ji and John R. Wible and Chong-xi Yuan},
  pages={1934 - 1940}
Derived features of a new boreosphenidan mammal from the Lower Cretaceous Yixian Formation of China suggest that it has a closer relationship to metatherians (including extant marsupials) than to eutherians (including extant placentals). This fossil dates to 125 million years ago and extends the record of marsupial relatives with skeletal remains by 50 million years. It also has many foot structures known only from climbing and tree-living extant mammals, suggesting that early crown therians… 

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A new Cretaceous Metatherian mammal from Henan, China

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Tribosphenic mammal from the North American Early Cretaceous

  • R. Cifelli
  • Environmental Science, Geography
  • 1999
A new tribosphenic mammal from the Early Cretaceous of North America is described, based on an unusually complete specimen, and its molar structure is primitive, emphasizing the need for caution in interpretation of isolated teeth.

Dual origin of tribosphenic mammals

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A new symmetrodont mammal from China and its implications for mammalian evolution

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A Chinese triconodont mammal and mosaic evolution of the mammalian skeleton

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Late Cretaceous relatives of rabbits, rodents, and other extant eutherian mammals

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Eutherian mammals from the Early Cretaceous of Mongolia

A collection of eutherian mammals consisting of 39 specimens (teeth and jaw fragments) from the ?Aptian or Albian Khoboor Beds in the Gobi Desert, Mongolia, is described. It contains 3 taxa:

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Comparison of the skulls of Mayulestes, Andinodelphys and Pucadelphys, from the early Palaeocene epoch of Bolivia are the oldest known for American marsupials and basicranial anatomy suggests that dog-like marsupial are closely related to an early didelphimorphian radiation in South America, rather than to Asiatic, North American, North America, or Australian lineages.