Phosphatized acanthomorphic acritarchs and related microfossils from the Ediacaran Doushantuo Formation at Weng'an (South China) and their implications for biostratigraphic correlation

The Doushantuo Formation at Weng'an in Guizhou Province, South China, is best known for animal embryo-like microfossils preserved in phosphorites. However, this unit also contains a diverse assemblage of three-dimensionally phosphatized acanthomorphic acritarchs, which are useful in the biostratigraphic subdivision and correlation of the lower–middle Ediacaran System. These acritarchs can be studied using both thin sectioning and acid maceration techniques, thus have the potential to resolve taxonomic inconsistencies between acritarchs preserved in cherts and shales. This paper presents a systematic treatment of acanthomorphs (and related spheroidal microfossils) from the Doushantuo Formation at Weng'an. More than 40 distinct species are described, including the following new species:Asterocapsoides robustusn. sp.,Knollisphaeridium?bifurcatumn. sp.,Megasphaera cymbalan. sp.,Megasphaera patellan. sp.,Megasphaera puncticulosan. sp.,Mengeosphaera eccentrican. gen. n. sp.,Papillomembrana boletiformisn. sp.,Sinosphaera variabilisn. sp.,Tanarium victorn. sp.,Tianzhushania raran. sp.,Variomargosphaeridium gracilen. sp., andWeissiella brevisn. sp. The Weng'an microfossil assemblage is dominated byMegasphaeraandMengeosphaerabut shares some taxa that are characteristic of theTianzhushania spinosabiozone and theTanarium conoideum–Hocosphaeridium scaberfacium–Hocosphaeridium anozosbiozone recognized in the Yangtze Gorges area. It may represent a transitional assemblage between these two biozones. The Weng'an microfossil assemblage also shares some elements with Ediacaran acanthomorph assemblages from Australia, Siberia, and East European Platform, indicating at least partial biostratigraphic overlap with those assemblages. Among the taxa described here,T. spinosaandH. anozosemerges as easily recognizable and widely distributed acanthomorph species whose first appearance may be used to define acanthomorph biozones for regional and global biostratigraphic correlation of lower–middle Ediacaran successions.

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Ediacaran Acanthomorphic Acritarchs and Other Microfossils from Chert Nodules of the Upper Doushantuo Formation in the Yangtze Gorges Area, South China

Journal of Paleontology ◽

10.1666/13-009 ◽

2014 ◽

Vol 88 (S72) ◽

pp. 1-139 ◽

Cited By ~ 45

Author(s):

Pengju Liu ◽

Shuhai Xiao ◽

Chongyu Yin ◽

Shouming Chen ◽

Chuanming Zhou ◽

...

Keyword(s):

South China ◽

Doushantuo Formation ◽

Systematic Treatment ◽

East European ◽

Northern India ◽

Systematic Paleontology ◽

First Occurrence ◽

Biostratigraphic Subdivision ◽

Multicellular Organisms ◽

Algal Thalli

Silicified microfossils preserved in chert nodules of the Doushantuo Formation in the Yangtze Gorges area of South China have great potential to improve the biostratigraphic subdivision and correlation of the Ediacaran System. This potential can be realized only if solid taxonomy is available. However, a systematic treatment of these microfossils (particularly acanthomorphic acritarchs) is lacking, greatly limiting their biostratigraphic potential. This paper presents the systematic paleontology of silicified microfossils from upper Doushantuo Formation (Member III) chert nodules at three sections in the Yangtze Gorges area. More than 90 species of microfossils are described, including 66 named taxa of acanthomorphs, seven named taxa of sphaeromorphs, 12 taxa of cyanobacterial filaments and coccoids, four taxa of algal thalli, and two species of tubular microfossils. Several acritarch species, includingAppendisphaera clavan. sp.,Mengeosphaera grandispinan. sp.,M. stegosauriformisn. sp.,Leiosphaeridia, and possiblySinosphaera rupina, are shown to be multicellular organisms, consistent with the proposition that some Ediacaran acritarchs may be diapause eggs of early animals. This study supports the view that theTianzhushania spinosaacanthomorph biozone is unique to the lower Doushantuo Formation in South China (and perhaps its equivalent in northern India) and that Ediacaran acanthomorph assemblages from Australia, Siberia, and East European Platform are younger than theTianzhushania spinosabiozone. It is proposed that the first occurrence ofHocosphaeridium anozos, a species with easily recognizable morphology and wide taphonomic and geographic distributions, be used to define the second Doushantuo acanthomorph biozone succeeding theTianzhushania spinosabiozone. New taxa described in this paper include three new genera (Bispinosphaeran. gen.;Yushengian. gen.; andGranitunican. gen.) and 40 new species:Appendisphaera?brevispinan. sp.,A. clavan. sp.,A.?hemisphaerican. sp.,A. longispinan. sp.,A. setosan. sp.,Bispinosphaera peregrinan. gen. n. sp.,Crinita paucispinosan. sp.,Ericiasphaera densispinan. sp.,Hocosphaeridium dilatatumn. sp.,Knollisphaeridium denticulatumn. sp.,K. longilatumn. sp.,K. obtusumn. sp.,K. parvumn. sp.,Mengeosphaera angustan. sp.,M. bellulan. sp.,M.cf.bellulan. sp.,M. constrictan. sp.,M.?cuspidatan. sp.,M.?gracilisn. sp.,M. grandispinan. sp.,M. latibasisn. sp.,M. miniman. sp.,M. spicatan. sp.,M. spinulan. sp.,M. stegosauriformisn. sp.,M. triangularisn. sp.,M. uniformisn. sp.,Sinosphaera asteriformisn. sp.,Tanarium acusn. sp.,T. elegansn. sp.,T. longitubularen. sp.,T.?minimumn. sp.,T. obesumn. sp.,T. variumn. sp.,Urasphaera fungiformisn. sp.,U. nuptan. sp.,Yushengia ramispinan. gen. n. sp.,Granitunica mcfaddeniaen. gen. n. sp.,Osculosphaera arcelliformisn. sp., andO. membraniferan. sp.

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The biostratigraphic succession of acanthomorphic acritarchs of the Ediacaran Doushantuo Formation in the Yangtze Gorges area, South China and its biostratigraphic correlation with Australia

Precambrian Research ◽

10.1016/j.precamres.2011.07.009 ◽

2013 ◽

Vol 225 ◽

pp. 29-43 ◽

Cited By ~ 49

Author(s):

Pengju Liu ◽

Chongyu Yin ◽

Shouming Chen ◽

Feng Tang ◽

Linzhi Gao

Keyword(s):

South China ◽

Doushantuo Formation ◽

Biostratigraphic Correlation

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Oxygen isotope geochemistry of phosphorite and dolomite and palaeo-ocean temperature estimation: A case study from the Neoproterozoic Doushantuo Formation, Guizhou Province, South China *

Progress in Natural Science Materials International ◽

10.1080/10020070412331343181 ◽

2004 ◽

Vol 14 (1) ◽

pp. 77-84 ◽

Cited By ~ 5

Author(s):

Hongfei Ling ◽

Shaoyong Jiang ◽

Hongzhen Feng ◽

Yongquan Chen ◽

Jianhua Chen ◽

...

Keyword(s):

Oxygen Isotope ◽

South China ◽

Isotope Geochemistry ◽

Guizhou Province ◽

Ocean Temperature ◽

Doushantuo Formation ◽

Temperature Estimation

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Acritarchs from the Doushantuo Formation at Liujing section in Songlin area of Guizhou Province, South China: Implications for early–middle Ediacaran biostratigraphy

Precambrian Research ◽

10.1016/j.precamres.2019.105453 ◽

2019 ◽

Vol 334 ◽

pp. 105453 ◽

Cited By ~ 3

Author(s):

Xiaodong Shang ◽

Pengju Liu ◽

Małgorzata Moczydłowska

Keyword(s):

South China ◽

Guizhou Province ◽

Doushantuo Formation

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A new SIMS zircon U–Pb date from the Ediacaran Doushantuo Formation: age constraint on the Weng'an biota

Geological Magazine ◽

10.1017/s0016756816001175 ◽

2017 ◽

Vol 154 (6) ◽

pp. 1193-1201 ◽

Cited By ~ 27

Author(s):

CHUANMING ZHOU ◽

XIAN-HUA LI ◽

SHUHAI XIAO ◽

ZHONGWU LAN ◽

QING OUYANG ◽

...

Keyword(s):

South China ◽

Guizhou Province ◽

Doushantuo Formation ◽

Algal Thalli ◽

Global Glaciation

AbstractAs a well-known phosphatized Lagerstätte, the Ediacaran Weng'an biota in central Guizhou Province of South China contains diverse acanthomorphic acritarchs, algal thalli, tubular microfossils as well as various spheroidal fossils. These fossils provide crucial palaeontological evidence for the radiation of multicellular eukaryotes after the termination of the Neoproterozoic global glaciation. While the Weng'an biota is generally considered as early Ediacaran in age on the basis of phosphorite Pb–Pb isochron ages ranging from 572 Ma to 599 Ma, the reliability and accuracy of these age data have been questioned and some geologists have proposed that the Weng'an biota may be younger than 580 Ma instead. Here we report a SIMS zircon U–Pb age of 609 ± 5 Ma for a tuffaceous bed immediately above the upper phosphorite unit in the Doushantuo Formation at Zhangcunping, Yichang, South China. Litho-, bio- and chemostratigraphic correlations suggest that the upper phosphorite unit at Zhangcunping can be well correlated with the upper phosphorite unit at Weng'an, which is the main horizon of the Weng'an biota. We therefore conclude that the Weng'an biota could be as old as 609 ± 5 Ma.

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