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  • Organic-walled microfossils from the Ediacaran Sete Lagoas Formation, Bambuí Group, Southeast Brazil: taxonomic and biostratigraphic analyses
Title: Organic-walled microfossils from the Ediacaran Sete Lagoas Formation, Bambuí Group, Southeast Brazil: taxonomic and biostratigraphic analyses
Abstract This work presents a detailed taxonomic study on organic-walled microfossils from the Ediacaran Sete Lagoas Formation (Bambuí Group) at the Barreiro section in the Januária area of the São Francisco basin, Brazil. Seven species are described, includingSiphonophycus robustum(Schopf, 1968),Ghoshia januarensisnew species,Leiosphaeridia crassa(Naumova, 1949),Leiosphaeridia jacutica(Timofeev, 1966),Leiosphaeridia minutissima(Naumova, 1949),Leiosphaeridia tenuissimaEisenack, 1958, and Germinosphaera bispinosaMikhailova, 1986. These taxa are recovered for the first time in the Sete Lagoas Formation. They occur abundantly in the lower portion of the studied section, but onlyGhoshia januarensisis present in the upper part of the studied section, probably due to environmental or taphonomic changes.Leiosphaeridiaspecies, particularlyLeiosphaeridia minutissima, dominate the organic-walled microfossil assemblage. Although most taxa described here have long stratigraphic ranges, they are consistent with a terminal Ediacaran age as inferred from detrital zircon data and tubular fossils (e.g.,CloudinaandCorumbella) from the Sete Lagoas Formation. UUID:http://zoobank.org/7f92b900-0176-4da6-93a3-fd51edb22cbf  more » « less
Award ID(s):
2021207
PAR ID:
10540438
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
Cambridge University Press
Date Published:
Journal Name:
Journal of Paleontology
ISSN:
0022-3360
Page Range / eLocation ID:
1 to 25
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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