6/22/2023 0 Comments Affinity 56Chuaria circularis from the early Mesoproterozoic Suket Shale, Vindhyan Supergroup, India: Insights from light and electron microscopy and pyrolysis-gas chromatography. J Palaeontol Soc Ind, 2003, 48 139–154ĭutta S, Steiner M, Banerjee S, et al. Carbonaceous megafossils from the Neoproterozoic Bhander Group, Central India. Hefei: University of Science and Technology of China Press, 2002 Doushantuo Fossils: Life on the Eve of Animal Radiation. Mesoproterozoic megafossil Chuaria-Tawuia association may represent parts of a multicellular plant, Vindhyan Supergroup, Central India. Discovery of carbonaceous compressions and their multicellular tissues from the Changzhougou Formation (1800 Ma) in the Yanshan Range, North China. Carbonaceous megaremains from the Neoproterozoic Owk Shales Formation of the Kurnool Group, Andhra Pradesh, India. Chuaria circularis Walcott 1899 - “megasphaeromorph acritarch” or prokaryotic colony? Acta Univ Carol Geol, 1997, 40: 645–665 Die neoproterozoischen Megaalgen Südchinas. New York: Columbia University Press, 1994. Proterozoic carbonaceous compressions (“metaphytes” and “worms”). Ultrastructure of Chuaria (Walcott) Vidal and Ford (Acritarch) from the Late Proterozoic Pendjari Formation, Benin and Burkina-Faso, West Africa. Palaeontology and biostratigraphy of late Precambrian macroscopic colonial algae: Chuaria Walcott and Tawuia Hofmann. The Mid-Proterozoic Little Dal macrobiota, Mackenzie Mountains, Northwest Canada. Late Precambrian algal megafossils Chuaria and Tawuia in some areas of eastern China. Bull Tianjin Inst Geol Min Res, 1980, 1: 49–69ĭuan C. A new occurrence of fossil group of Chuaria from the Sinian System in north Anhui and its geological meaning. Über die Wandstructuren sphaeromorpher Acritarchen: Tasmanites Newton, Tapajonites Sommer and van Bökel, Chuaria Walcott. circularis Walcott from the Precambrian Hector Formation, Banff National Park, Alberta, Canada. This study partially resolves the century-long controversy over the affinity of Chuaria, and makes Chuaria one of the few recognized multicellular eukaryotes before the Neoproterozoic glaciation. Membrane-like structures within the cells (the first to be reported in Precambrian fossils) imply a eukaryotic nature. Different thicknesses of cell walls suggest primary cellular differentiation in this organism. The cell walls in Chuaria suggest that it is a multicellular eukaryotic alga, in agreement with the latest biogeochemical analyses. In this paper the cellular details of Chuaria are clearly revealed for the first time. Although often treated as a multicellular alga, this interpretation remains inconclusive because the lacking unambiguous demonstration of cellular structures. Many mutually exclusive affinities have been suggested for this frequently encountered fossil. It is perhaps the most controversial fossil in term of its affinity despite more than one hundred years of study. Chuaria is one of the few globally distributed macrofossil pioneers documented in the Precambrian.
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