—Well-preserved microfossils occur in abundance through more than 1000m of lower Mesoproterozoic siliciclastic rocks composing the Roper Group, Northern Territory, Australia. The Roper assemblage includes 34 taxa, five interpreted unambiguously as eukaryotes, nine as possible eukaryotes (including Blastanosphaira kokkoda new genus and new species, a budding spheromorph with thin chagrinate wall...

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Synurophytes, also known as scaled chrysophytes, are ecologically important algae that produce an array of siliceous structures upon which their taxonomy is based. Despite occupying a key position within the photosynthetic heterokonts, the evolutionary history of synurophytes remains poorly constrained. Here, modern and Middle Eocene siliceous scales of the morphotaxon Mallomonas insignis are u...

For the lithostratigraphy and microbiostratigraphical studies, a stratigraphical section (named Dareh-Goshayesh) has selected and is located in southeast of Maragheh city, south of eastern Azerbaijan province in the northwest of Iran. The thickness of successions in the selected stratigraphic section is measured about 223.6 m. The mentioned studied stratigraphic section is composed of two clast...