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Marine and non-marine strata preserving Ediacaran microfossils.

ABSTRACT: We report the first occurrence of microfossils in Ediacaran strata of the Camaquã Basin. The assemblage includes simple (Leiosphaeridia sp. predominantly) and ornamented acritarchs associated with microbial mats. They are related to the Ediacaran Complex Acanthomorph Palynoflora (ECAP) and Late Ediacaran Leiosphere Palynoflora (LELP) due to the similar morphology and time interval assigned to those assemblages, though the observed specimens are a lot simpler and less diversified. However, different from the usual occurrences, this case study reports Neoproterozoic cosmopolitan communities living in marine (basal unit) and lacustrine (middle units) settings. Fossils within non-marine strata in the Precambrian record are rare. Therefore, this first finding of microfossils in the Camaquã Basin constitutes a new piece of the puzzle related to the history of the Panafrican-Brasiliano basins and shed some light on possible settings where the Ediacaran eukaryotes have evolved.

SUBMITTER: Lehn I

PROVIDER: S-EPMC6614404 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature

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Marine and non-marine strata preserving Ediacaran microfossils.

Lehn Ilana I Horodyski Rodrigo Scalise RS Paim Paulo Sérgio Gomes PSG

Scientific reports 20190708 1

We report the first occurrence of microfossils in Ediacaran strata of the Camaquã Basin. The assemblage includes simple (Leiosphaeridia sp. predominantly) and ornamented acritarchs associated with microbial mats. They are related to the Ediacaran Complex Acanthomorph Palynoflora (ECAP) and Late Ediacaran Leiosphere Palynoflora (LELP) due to the similar morphology and time interval assigned to those assemblages, though the observed specimens are a lot simpler and less diversified. However, differ ...[more]

PMID: 31285486

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