Yixian Formation

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The Yixian Formation is a geological formation in Liaoning, People's Republic of China, that stems from the early Cretaceous period. It is known for its fossils. It was initially recognized during the time the Japanese Empire controlled a large chunk of Manchuria (Northern China) called "Jehol". During the occupation of Jehol, many Japanese scientists had noticed fossil remains of extinct fish and reptiles, possibly the champsosaurs. These initial fossil discoveries made by Japanese scientists vanished from history once World War II ended in 1945. By 1949, when administration of the area passed to the Communist Party and its leader Mao Tse-Tung, the fossils of Yixian were studied only by Chinese scientists. It was not until the 1990s when remarkable fossils of birds and dinosaurs were excavated. Since 1996, a number of dinosaur fossils that have revolutionized our knowledge of these animals have been found at Yixian; among them are the first known non-avian theropods with feathers.

Contents

[edit] Fossil taxa

Fossils found at Yixian include:

[edit] Dinosaurs (including birds)

Theropods

Cerapods

Thyreophorans

[edit] Pterosaurs

[edit] Mammals

Symmetrodonts

Triconodonts

Multituberculates

Metatheria (marsupials)

Eutheria (placental mammals)

[edit] Other vertebrates

Lepidosaurians

Choristoderans

Turtles

  • Manchurochelys

Amphibians

  • Jeholotriton, a gilled salamander
  • Callobatrachus, a frog
  • Mesophryne, a frog with no known living relatives

Fish

[edit] Insects and other arthropods

[edit] Plants

[edit] See Also

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