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ephedroids from the Early Cretaceous Yixian Formation in Liaoning ...

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262 C. Ryd<strong>in</strong> et al.: <strong>Cretaceous</strong> <strong>ephedroids</strong> <strong>from</strong> Ch<strong>in</strong>a<br />

Drewria (Crane and Upchurch 1987), Gurvanella<br />

(Chaoyangia) (Krassilov 1982, Duan<br />

1998) and undescribed fossils <strong>from</strong> Brazil<br />

(Barbara Mohr, unpubl. data) and Ch<strong>in</strong>a<br />

(Ryd<strong>in</strong> et al., unpubl. data).<br />

Whe<strong>the</strong>r <strong>the</strong> ephedroid fossils presented<br />

here belong to crown group Gnetales or to<br />

ext<strong>in</strong>ct stem groups, is yet to be discovered. We<br />

consider <strong>the</strong>m members of <strong>the</strong> ephedran l<strong>in</strong>eage,<br />

but due to restricted <strong>in</strong>formation <strong>in</strong> <strong>the</strong> fossils<br />

and poorly understood morphological diversity<br />

of extant Ephedra, it is not possible to assign<br />

<strong>the</strong>m to any particular subgroup of Ephedra or<br />

to clearly exclude <strong>the</strong>m <strong>from</strong> <strong>the</strong> extant genus.<br />

The authors thank Susana Magallo´n and an<br />

anonymous reviewer for valuable comments on <strong>the</strong><br />

text, Chen Peiji for <strong>in</strong>formation on <strong>the</strong> geology of<br />

<strong>the</strong> <strong>Yixian</strong> <strong>Formation</strong>, Arne Anderberg for nomenclatural<br />

comments and suggestions and Yvonne<br />

Arremo for assistance with photography. The<br />

project was supported by grants <strong>from</strong> <strong>the</strong> Swedish<br />

Research Council (EMF), The Asian-Swedish<br />

Research L<strong>in</strong>k Programme (EMF and Zhou Zhonghe),<br />

NSFC (SQW) and <strong>from</strong> <strong>the</strong> Royal Swedish<br />

Academy of Sciences (CR).<br />

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