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Skeletogenesis and asexual reproduction in the earliest biomineralizing animal Cloudina
Geology, 2005The tubular fossil Cloudina is emerging as an important Ediacaran index fossil. How- ever, its morphology, skeletogenesis, reproduction, and phylogenetic affinity have not been fully resolved. New material from the Dengying Formation of south China confirms that Cloudina tubes consist of eccentrically and sometimes deeply nested funnels and that the ...
H. Hua +4 more
semanticscholar +2 more sources
Extinction of Cloudina and Namacalathus at the Precambrian-Cambrian boundary in Oman
Geology, 2003Biostratigraphic, carbon isotope, and U-Pb zircon geochronological data from the Ara Group of Oman indicate an abrupt last appearance of Cloudina and Namacalathus coincident with a large-magnitude, but short-lived negative excursion in the carbon isotope composition of seawater that is globally coincident with the Precambrian-Cambrian boundary.
J. Amthor +6 more
semanticscholar +5 more sources
Taxonomy of the late Ediacaran index fossil Cloudina and a new similar taxon from South China
Precambrian Research, 2017Abstract Cloudina is a late Ediacaran tubular fossil known from almost every continent. It is typically a mm- to cm-sized conical tube consisting of multiple, nested, funnel-shaped elements, forming the diagnostic “funnel-in-funnel” tube construction.
Yaoping Cai +3 more
semanticscholar +2 more sources
A new species of Cloudina from the terminal Ediacaran of Spain
Precambrian Research, 2010Abstract The terminal Ediacaran genus Cloudina includes some of the earliest biomineralized fossils. It consists of a tube formed by stacked funnel-shaped elements, and is usually interpreted as the external skeleton of an early metazoan. Although a number of species have been described within this genus, their distinctiveness remains unclear and ...
I. Cortijo +3 more
semanticscholar +3 more sources
Some observations on Cloudina, a terminal Proterozoic index fossil from Namibia
Journal of African Earth Sciences, 2001An overview is provided of past and present concepts about Cloudina, a Neoproterozoic tube-building organism, significant for its early use of biomineralisation. In the past, Cloudina tubes from the Nama limestones of Namibia have had to be studied in thin- or polished sections, but some observations are reported here on silicified tubes extracted ...
C. K. Brain
semanticscholar +2 more sources
Gondwana Research, 2014
Abstract Cloudina are important Ediacaran index fossils, as they have a consistent terminal Neoproterozoic age and a worldwide distribution. The morphology of Cloudina has been reconstructed primarily on the basis of three-dimensionally preserved Chinese and Spanish specimens, but questions remain surrounding their phylogenetic placement ...
Yaoping Cai +4 more
semanticscholar +2 more sources
Abstract Cloudina are important Ediacaran index fossils, as they have a consistent terminal Neoproterozoic age and a worldwide distribution. The morphology of Cloudina has been reconstructed primarily on the basis of three-dimensionally preserved Chinese and Spanish specimens, but questions remain surrounding their phylogenetic placement ...
Yaoping Cai +4 more
semanticscholar +2 more sources