Liaoxia cao et SQ Wu (Gnetales): Ephedroids from the Early Cretaceous Yixian Formation in Liaoning, Northeastern China

doi:10.1007/s00606-006-0481-2

	Liaoxia cao et SQ Wu (Gnetales): Ephedroids from the Early Cretaceous Yixian Formation in Liaoning, Northeastern China
	Rydin, C.; Wu, S. Q.; Friis, E. M.
	2006-12-01
发表期刊	PLANT SYSTEMATICS AND EVOLUTION
ISSN	0378-2697
卷号	262 期号:3-4 页码:239-265
摘要	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.
关键词	Ephedra Liaoxia Gnetales Yixian Formation fossils Early Cretaceous China Jehol Biota
DOI	10.1007/s00606-006-0481-2
语种	英语
关键词[WOS]	LAKE BAIKAL AREA ; EUCOMMIIDITES POLLEN ; SEED PLANTS ; SP NOV. ; ANGIOSPERM ; FOSSIL ; EPHEDRACEAE ; ONTOGENY ; AGE ; ARCHAEFRUCTUS
WOS研究方向	Plant Sciences ; Evolutionary Biology
WOS类目	Plant Sciences ; Evolutionary Biology
WOS记录号	WOS:000243093600007
出版者	SPRINGER WIEN
文献类型	期刊论文
条目标识符	http://ir.nigpas.ac.cn/handle/332004/583
专题	中国科学院南京地质古生物研究所
通讯作者	Rydin, C.
作者单位	1.Swedish Museum Nat Hist, Dept Palaeobiol, S-10405 Stockholm, Sweden 2.Chinese Acad Sci, Nanjing Inst Geol & Palaeontol, Nanjing 210008, Peoples R China
推荐引用方式 GB/T 7714	Rydin, C.,Wu, S. Q.,Friis, E. M.. Liaoxia cao et SQ Wu (Gnetales): Ephedroids from the Early Cretaceous Yixian Formation in Liaoning, Northeastern China[J]. PLANT SYSTEMATICS AND EVOLUTION,2006,262(3-4):239-265.
APA	Rydin, C.,Wu, S. Q.,&Friis, E. M..(2006).Liaoxia cao et SQ Wu (Gnetales): Ephedroids from the Early Cretaceous Yixian Formation in Liaoning, Northeastern China.PLANT SYSTEMATICS AND EVOLUTION,262(3-4),239-265.
MLA	Rydin, C.,et al."Liaoxia cao et SQ Wu (Gnetales): Ephedroids from the Early Cretaceous Yixian Formation in Liaoning, Northeastern China".PLANT SYSTEMATICS AND EVOLUTION 262.3-4(2006):239-265.