Microfossils from Neoproterozoic Supersequence 1 of the Officer Basin,Western Australia

The discovery of a rich assemblage of microfossils from the Neoproterozoic western Officer Basin (Centralian Superbasin) provides a more complete understanding of the biostratigraphy of this Basin. The microfossils are found in Supersequence 1 (～800 Ma) in Western Australia. The assemblages are comprised of acritarchs and cyanobacteria isolated by acid maceration from siliciclastics of the Browne (Madley), Hussar, Kanpa and Steptoe Formations. The distinctive acritarchs Cerebrosphaera buickii, Satka colonialica, Stictosphaeridium sinapticuliferum and Pterospermopsimorpha insolita are of particular interest in the Neoproterozoic. These taxa are found in similar depositional environments in Spitsbergen, Arizona, Canada and Siberia. This evidence, together with lithostratographic correlations, isotope chemostratigraphy, and sequence analysis contributes to the continuing development of Neoproterozoic stratigraphy.     

Neoproterozoic microfossils from the Officer Basin,Western Australia

Microfossil assemblages are described from the early Neoproterozoic Madley and Browne Formations, western Officer Basin. One chert and eleven siliciclastic samples yielded microfossils. Myxococcoides cantabrigiensis occurs as pustular mats in the chert sample and Eomicrocystis malgica, Pterospermopsimorpha granulata, Skiagia sp. cf. S. pusilla, and undetermined species of Obruchevella, Heliconema, and Trachystrichosphaera are present in acid macerated samples. Leiosphaeridia spp. and Siphonophycus spp. are also found in fine-grained siliciclastic samples, with clusters of Synsphaeridium sp. in some samples. These findings enable a more substantial reconstruction of the palaeoenvironment of Supersequence 1 in the western Centralian Superbasin. The acanthomorph acritarchs are considered to be planktonic eucaryotes washed into environments which ranged from coastal sabkha through to tidal flats, which may be the source of the prokaryotic, benthic, matforming cyanobacteria.     

Dendroid multicellular thallophytes preserved in a Neoproterozoic black phosphorite in southern China

Du, W., Wang, X.L., Komiya, T., Zhao, R. & Wang, Y., April 2016. Dendroid multicellular thallophytes preserved in a Neoproterozoic black phosphorite in southern China. Alcheringa 40, xxx–xxx. ISSN 0311-5518.

A new form of dendroid multicellular thallophyte is documented in the Ediacaran Doushantuo phosphorite at Weng’an, Guizhou Province, southern China. The dendroid thallophytes have variable forms, possibly owing to heteromorphic variation. Many lateral branches extend from the upper portions of the main axes; the lateral branches bear terminal vegetative vesicles, reproductive vesicles, monosporangium-like discoidal vesicles and urn-shaped pseudoparenchymatous structures. The vegetative vesicles give rise to clavate pseudoparenchymatous structures, characterized by differentiation of the thallus medulla/cortex, which might represent an early stage of thallus development. An oogamous conceptacle arising from one carpogonial vesicle forms a highly specialized goblet-shaped conceptacle. The discovery of the new dendroid multicellular thallophytes provides not only the first fossil-based evidence of the morphological complexity and tissue differentiation in the Precambrian organisms but also insights into the life cycle of the Precambrian red algae.

Wei Du* [duwei@ea.c.u-tokyo.ac.jp], School of Earth Sciences and Resources, China University of Geosciences, Beijing, PR China; Xun Lian Wang [wxl@cugb.edu.cn], School of Earth Sciences and Resources, China University of Geosciences, Beijing, 100083, PR China; Tsuyoshi Komiya [komiya@ea.c.u-tokyo.ac.jp], Graduate School of Arts and Sciences, University of Tokyo, Tokyo 153-8902, Japan. Ran Zhao [zhao_ran13@eps.s.u-tokyo.ac.jp], Department of Earth and Planetary Science, University of Tokyo, Tokyo 113-0033, Japan. Yue Wang [gzyuewang@126.com], School of Resources and Environments, Guizhou University, Guiyang, 550025, PR China. *Also affiliated with Graduate School of Arts and Sciences, University of Tokyo, Tokyo 153-8902, Japan.     

Taphonomy of Corumbella werneri from the Ediacaran of Brazil: sinotubulitid tube or conulariid test?

Walde, D.H.-G., Weber, B., Erdtmann, B.-D. & Steiner, M. 20 June 2019. Taphonomy of Corumbella werneri from the Ediacaran of Brazil: sinotubulitid tube or conulariid test? Alcheringa 43, 335–350. ISSN 0311-5518

The problematic late Ediacaran tubular fossil Corumbella werneri is revised based on two-dimensional compressions, and new three-dimensionally preserved specimens from the Tamengo Formation of the Corumbá Region in Mato Grosso do Sul, west-central Brazil. These fossils represent some of the oldest skeletonized metazoans and were originally described from diagenetically compacted tubes that prompted conflicting interpretations as either Ediacaran coronate scyphozoan exoskeletons, or conulariid tests. Our new material from Corumbá permits a morphological and taphonomic revision of C. werneri, which we suggest was probably a calcareous sinotubulitid. Corumbella werneri closely resembles the late Ediacaran Sinotubulites from South China, as well as the Silurian worm tube Eoalvinellodes, which has similar exterior ornamentation. Ultrastructurally, the tubes of C. werneri exhibit a coarse sparitic microtexture, which we attribute to diagenetic alteration. Partial flexibility also supports interpretation as an originally weakly calcified, or entirely organic exoskeleton. We therefore reject placement of C. werneri as a conulariid scyphozoan, and instead, advocate possible relationships with marine annelids.

Detlef Hans-Gert Walde [walde.detlef@gmail.com], University of Brasília, Institute of Geosciences, Brasília-DF, Brazil; Bernd Weber [bweber@zedat.fu-berlin.de], Freie Universität Berlin, Institut für Geologische Wissenschaften, Malteserstr. 74–100, D-12249 Berlin, Germany; Bernd-D. Erdtmann [berni1739@gmail.com], 1165 N Mountain View Road, Apache Junction, AZ 85119, USA; *Michael Steiner [Michael.Steiner@FU-Berlin.de], Freie Universität Berlin, Institut für Geologische Wissenschaften (Haus D), Malteserstr. 74–100, D-12249 Berlin, Germany.     

A preliminary report on new Ediacaran fossils from Iran

Vickers-Rich, P., Soleimani, S., Farjandi, F., Zand, M., Linnemann, U., Hofmann, M., Wilson, S.A., Cas, R. &; Rich, T.H. November, 2017. A preliminary report on new Ediacaran fossils from Iran. Alcheringa 42, 231–244. ISSN 0311-5518.

Recent exploratory field mapping of marine sedimentary sequences in the Koushk Mine locality of the Bafq region in Central Iran, and on the northern slopes of the Elborz Mountains south of the Caspian Sea, has yielded large complex body and trace fossils of Neoproterozoic–early Cambrian age. The recovered specimens resemble the previously documented Precambrian discoidal form Persimedusites, and a the tubular morphotype Corumbella, which is a novel occurrence for Iran and otherwise only recorded before from Brazil and the western USA. Additional enigmatic traces can not yet be interpreted unequivocally, but suggest that future work may uncover more unusual Ediacaran fossils from various localities in Central Iran.

Patricia Vickers-Rich* [prich@swin.edu.au, pat.rich@monash.edu], Faculty of Science, Swinburne University of Technology, Melbourne (Hawthorn), Victoria 3122, Australia; Sara Soleimani [sara_soleimani@yahoo.com], Palaeontology Department, Geological Survey of Iran, Tehran, Iran; Farnoosh Farjandi [farnooshfarjandi@gmail.com], Department of Geochemical Exploration, Geological Survey of Iran, Tehran, Iran; Mehdi Zand [zand.mehdi.geo@gmail.com], Geology Department, Bafq Mining Company, Koushk Mine, Yazd, Iran. Ulf Linnemann [ulf.linnemann@senckenberg.de], and Mandy Hofmann [mandy.hofmann@senckenberg.de], Senckenberg Naturhistorische Sammlungen, Dresden, Museum für Mineralogie und Geologie, Sektion Geochronologie, Koenigsbruecker Landstrasse 159, D-01109, Dresden, Germany; Siobhan A. Wilson [sasha.wilson@monash.edu], School of Earth, Atmosphere and Environment, Monash University, Melbourne (Clayton), Victoria 3800, Australia; Raymond Cas [ray.cas@monash.edu], School of Earth, Atmosphere and Environment, Monash University, Melbourne (Clayton), Victoria 3800, Australia; Thomas H. Rich? [trich@museum.vic.gov.au], Museum Victoria, Exhibition Gardens, PO Box 666, Melbourne, Victoria, 3001 Australia. *Also affiliated with: School of Earth, Atmosphere and Environment, Monash University, Melbourne (Clayton), Victoria 3800, Australia; School of Environmental Sciences, Deakin University, Melbourne (Burwood), Victoria, Australia 3125; Palaeontology Department, Museum Victoria, Carlton Gardens, PO Box 666, Melbourne, Victoria 3001, Australia. ?Also affiliated with: School of Earth, Atmosphere and Environment, Monash University, Melbourne (Clayton), Victoria 3800, Australia; Faculty of Science, Swinburne University of Science and Technology, Melbourne (Hawthorn), Victoria 3122, Australia.