Plant Systematics and Evolution

, Volume 262, Issue 3, pp 239–265

Liaoxia Cao et S.Q. Wu (Gnetales): ephedroids from the Early Cretaceous Yixian Formation in Liaoning, northeastern China


DOI: 10.1007/s00606-006-0481-2

Cite this article as:
Rydin, C., Wu, S.Q. & Friis, E.M. Plant Syst. Evol. (2006) 262: 239. doi:10.1007/s00606-006-0481-2


Gnetalean compression-impression fossils are described from the Early Cretaceous Yixian Formation, Liaoning Province, north-eastern China, and assigned to six species of Liaoxia Cao et S.Q. Wu. The fossils have opposite-decussate phyllotaxis and cones comprising 2–12 pairs of bracts. Ovulate cones have seeds typically in a distal position. The species differ from each other and from previously described fossils in the absence or presence of leaves, shape of cones and seeds, and shape and position of cone bracts. The species of Liaoxia are probably close relatives of extant species of Ephedra L., but diagnostic reproductive details that could confirm this hypothesis are not preserved. The restricted information in the fossils and the poorly understood morphological diversity of extant Ephedra, prevent assignment of the fossils to any particular subgroup of Ephedra, as well as an explicit exclusion of them from the extant genus.


EphedraLiaoxiaGnetalesYixian FormationfossilsEarly CretaceousChinaJehol Biota

Copyright information

© Springer-Verlag Wien 2006

Authors and Affiliations

  1. 1.Department of PalaeobotanySwedish Museum of Natural HistoryStockholmSweden
  2. 2.Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjingChina