Silicified Horodyskia and Palaeopascichnus from upper Ediacaran cherts in South China: tentative phylogenetic interpretation and implications for evolutionary stasis

	Silicified Horodyskia and Palaeopascichnus from upper Ediacaran cherts in South China: tentative phylogenetic interpretation and implications for evolutionary stasis
	Dong, Lin 1; Xiao, Shuhai 1; Shen, Bing 1; Zhou, Chuanming 2
刊名	JOURNAL OF THE GEOLOGICAL SOCIETY
	2008
卷号	165 页码:367-378
ISSN号	0016-7649
文献子类	Article
英文摘要	Horodyskia is one of the earliest known macroscopic life forms, with a fossil record dating from c. 1.4 Ga. Palaeopascichnus represents a key Ediacaran element with world-wide distribution. However, their body constructions and affinities are poorly understood, partly because previously described species are mostly preserved as casts and moulds in siliciclastic rocks. Silicified specimens from the upper Ediacaran Liuchapo Formation in eastern Guizhou, South China, are described as Horodyskia minor sp. nov. and Palaeopascichnus jiumenensis sp. nov. Their taxonomic assignments are based on their uniserial arrangement of spheroidal or discoidal units, which are connected by a filament and surrounded by a quartz halo. They are unlikely to be brown algae, animal traces, faecal pellets, colonial metazoans, or giant sulphide-oxidizing bacteria. Instead, we propose that Horodyskia and Palaeopascichnus may be phylogenetically related, and their collective morphologies allow tentative comparison with agglutinated foraminifers: the segments can be compared with cytoplasm-filled chambers, connecting filament with small passage between chambers, and quartz haloes with agglutinated tests. However, their ontogeny appears to be distinct from that of modem foraminifers. The occurrences of Horodyskia fossils in Mesoproterozoic and Ediacaran rocks indicate an extremely long range (c. 900 Ma) and echoes the proposition of extended evolutionary stasis in the Proterozoic.
WOS关键词	NEOPROTEROZOIC DOUSHANTUO FORMATION ; BEDDING-PLANE MARKINGS ; U-PB GEOCHRONOLOGY ; BELT SUPERGROUP ; TRACE FOSSILS ; WESTERN-AUSTRALIA ; MONTANA ; FORAMINIFERA ; MICROFOSSILS ; EUKARYOTES
WOS研究方向	Geology
语种	英语
出版者	GEOLOGICAL SOC PUBL HOUSE
WOS记录号	WOS:000253287800029
内容类型	期刊论文
源URL	[http://ir.iggcas.ac.cn/handle/132A11/70018]
专题	中国科学院地质与地球物理研究所
通讯作者	Xiao, Shuhai
作者单位	1.Virginia Polytech Inst & State Univ, Dept Geosci, Blacksburg, VA 24061 USA 2.Chinese Acad Sci, Inst Geol & Palaeontol, State Key Lab Palaeobiol & Stratigraphy, Nanjing 210008, Peoples R China
推荐引用方式 GB/T 7714	Dong, Lin,Xiao, Shuhai,Shen, Bing,et al. Silicified Horodyskia and Palaeopascichnus from upper Ediacaran cherts in South China: tentative phylogenetic interpretation and implications for evolutionary stasis[J]. JOURNAL OF THE GEOLOGICAL SOCIETY,2008,165:367-378.
APA	Dong, Lin,Xiao, Shuhai,Shen, Bing,&Zhou, Chuanming.(2008).Silicified Horodyskia and Palaeopascichnus from upper Ediacaran cherts in South China: tentative phylogenetic interpretation and implications for evolutionary stasis.JOURNAL OF THE GEOLOGICAL SOCIETY,165,367-378.
MLA	Dong, Lin,et al."Silicified Horodyskia and Palaeopascichnus from upper Ediacaran cherts in South China: tentative phylogenetic interpretation and implications for evolutionary stasis".JOURNAL OF THE GEOLOGICAL SOCIETY 165(2008):367-378.