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Megasphaera

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Journal Article

Phosphatized Acanthomorphic Acritarchs and Related Microfossils from the Ediacaran Doushantuo Formation at Weng'an (South China) and their Implications for Biostratigraphic Correlation

Shuhai Xiao, Chuanming Zhou, Pengju Liu, Dan Wang, Xunlai Yuan
Published: 01 January 2014
Journal of Paleontology (2014) 88 (1): 1–67.
DOI: https://doi.org/10.1666/12-157R
...., Knollisphaeridium ? bifurcatum n. sp., Megasphaera cymbala n. sp., Megasphaera patella n. sp., Megasphaera puncticulosa n. sp., Mengeosphaera eccentrica n. gen. n. sp., Papillomembrana boletiformis n. sp., Sinosphaera variabilis n. sp., Tanarium victor n. sp., Tianzhushania rara n. sp., Variomargosphaeridium...
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PHOSPHATIZED ANIMAL EMBRYOS FROM THE NEOPROTEROZOIC DOUSHANTUO FORMATION AT WENG'AN, GUIZHOU, SOUTH CHINA

SHUHAI XIAO, ANDREW H. KNOLL
Published: 01 September 2000
Journal of Paleontology (2000) 74 (5): 767–788.
DOI: https://doi.org/10.1666/0022-3360(2000)074<0767:PAEFTN>2.0.CO;2
... to the genera Megasphaera and Parapandorina were originally interpreted as problematica and volvocacean green algae, respectively, but newly discovered populations support their reinterpretation as the eggs and embryos of early animals. The fossils' large size (about half a millimeter in diameter), persistent...
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Figure 3 — <b>Megasphaera</b> inornata ( 1–2, 4–5, 7, 11 ) and <b>Megasphaera</b> orna...

Figure 3 — Megasphaera inornata ( 1–2, 4–5, 7, 11 ) and Megasphaera orna...

Published: 01 September 2000
Figure 3 — Megasphaera inornata ( 1–2, 4–5, 7, 11 ) and Megasphaera ornata n. sp. ( 12 – 13 ). 1–2, 4–5, 7, 11, Megasphaera inornata Chen and Liu, 1986 . (For all fossil figures in this paper, a field number and a photo number are given for each SEM photograph; and a field number, a thin
Journal Article

Doushantuo-type microfossils from latest Ediacaran phosphorites of northern Mongolia

Ross P. Anderson, Francis A. Macdonald, David S. Jones, Sean McMahon, Derek E.G. Briggs
Journal: Geology
Published: 19 October 2017
Geology (2017) 45 (12): 1079–1082.
DOI: https://doi.org/10.1130/G39576.1
... assemblage. Eight genera include the second occurrence of the putative multicellular fossil animal embryo Megasphaera outside South China, the Doushantuo-Pertatataka–type acanthomorphic acritarchs h Cavaspina , and Variomargosphaeridium , and the possible alga Archaeophycus yunnanensis . The assemblage...
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Rare helical spheroidal fossils from the Doushantuo Lagerstätte: Ediacaran animal embryos come of age?

Shuhai Xiao, James W. Hagadorn, Chuanming Zhou, Xunlai Yuan
Journal: Geology
Published: 01 February 2007
Geology (2007) 35 (2): 115–118.
DOI: https://doi.org/10.1130/G23277A.1
... in a sculptured envelope that is very similar to that of Doushantuo animal eggs and blastula embryos such as Megasphaera ornata . A hallmark of these fossils is a three-dimensional spiral structure, which always consists of three clockwise coils, and occurs on both the envelope and the internal body. The spiral...
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SEM of <b>Megasphaera</b> cymbala n. sp. 1 , IGCAGS-051226-6121; 2 , IGCAGS-...

SEM of Megasphaera cymbala n. sp. 1 , IGCAGS-051226-6121; 2 , IGCAGS-...

Published: 01 January 2014
Figure 21 SEM of Megasphaera cymbala n. sp. 1 , IGCAGS-051226-6121; 2 , IGCAGS-051226-6114; 3 , IGCAGS-051226-6122; 4 , holotype, IGCAGS-051226-6113; 5 , IGCAGS-051226-6116; 6 , IGCAGS-050719-G42; 7–9 , magnified views of 4 (central part), 5 (central left part), and 6 (central
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SEM of <b>Megasphaera</b> ornata , showing tubercular ornamentation ( 1 ), tran...

SEM of Megasphaera ornata , showing tubercular ornamentation ( 1 ), tran...

Published: 01 January 2014
Figure 22 SEM of Megasphaera ornata , showing tubercular ornamentation ( 1 ), transitional form between tubercular and cerebral ornamentation ( 2 ), cerebral ornamentation ( 3 ), transitional form between tubercular, cerebral, and polygonal ornamentation ( 4, 5 ), polygonal ornamentation ( 6
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SEM of <b>Megasphaera</b> patella n. sp. 1 , holotype, NIGPAS-0629-4583; 2 ,...

SEM of Megasphaera patella n. sp. 1 , holotype, NIGPAS-0629-4583; 2 ,...

Published: 01 January 2014
Figure 23 SEM of Megasphaera patella n. sp. 1 , holotype, NIGPAS-0629-4583; 2 , magnified view of upper right part of 1 (rotated 90° counterclockwise); 3 , IGCAGS-080317-10; 4 , magnified view of central left part of 3 ; 5 , IGCAGS-050725-5810; 6 , magnified view of central upper
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SEM of <b>Megasphaera</b> puncticulosa n. sp. 1 , partial view of a large bag...

SEM of Megasphaera puncticulosa n. sp. 1 , partial view of a large bag...

Published: 01 January 2014
Figure 24 SEM of Megasphaera puncticulosa n. sp. 1 , partial view of a large bag-like structure with ∼30 vesicles, with black arrow pointing to holotype, HUHPC-64839 (WJY98-18E, 1181, stage 58-A1); 2 , magnified view of central part of 1 ; 3 , magnified view of central part of 2 ; 4
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Figure 1. Scanning electron micrograph (SEM) images of <b>Megasphaera</b> ornata ...

Figure 1. Scanning electron micrograph (SEM) images of Megasphaera ornata ...

in > Geology
Published: 01 February 2007
Figure 1. Scanning electron micrograph (SEM) images of Megasphaera ornata (A) and helical spheroidal fossils (B–S). A: Cerebral sculpture on Megasphaera ornata . B–D: Helical spheroidal fossils with cerebral sculpture and subtle spiral structures (arrows) on envelopes, expressed as shallow
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Figure 4 — <b>Megasphaera</b> ornata n. sp. 1 – 2, polygonal envelope ornament...

Figure 4 — Megasphaera ornata n. sp. 1 – 2, polygonal envelope ornament...

Published: 01 September 2000
Figure 4 — Megasphaera ornata n. sp. 1 – 2, polygonal envelope ornamentation. Note the secondary spherulitic overgrowth (arrowed) on internal body; 3 – 4, polygons with fractal branching; 5 – 6, tubercular envelope ornamentation; 7 – 10, tubercles with dimples at top (arrows in 10
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Figure 5 — <b>Megasphaera</b> ornata n. sp. ( 1–4 ) and Parapandorina raphospis...

Figure 5 — Megasphaera ornata n. sp. ( 1–4 ) and Parapandorina raphospis...

Published: 01 September 2000
Figure 5 — Megasphaera ornata n. sp. ( 1–4 ) and Parapandorina raphospissa ( 5–11 ). 1, K94-21, 248; 2, WJY-19E, 220; 3, WJY-19E, 284; 4, holotype (HUHPC-62990). Note the smooth internal body. SRA-1, 38; 5 – 7, two-cell stage; 8 – 11, possible two-cell stage. 5, Note the smooth
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Paleontology of Khesen Formation (northern Mongolia) revealed by 20% acetic...

Paleontology of Khesen Formation (northern Mongolia) revealed by 20% acetic...

in > Geology
Published: 19 October 2017
Figure 3. Paleontology of Khesen Formation (northern Mongolia) revealed by 20% acetic acid maceration. A: Archaeophycus yunnanensis showing T cell division, Yale Peabody Museum (YPM) specimen 538070. B–C: Cavaspina ? basiconica . B: YPM 538071. C: YPM 538072. D–E: Megasphaera sp. D: YPM
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Figure 10 —Globule size (shaded bars) and internal body size (open bars) i...

Figure 10 —Globule size (shaded bars) and internal body size (open bars) i...

Published: 01 September 2000
Figure 10 —Globule size (shaded bars) and internal body size (open bars) in Megasphaera spp., Parapandorina raphospissa, and Megaclonophycus onustus. This graph shows the constancy of globule size and the decreasing internal body size with increasing number of internal bodies (from left
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Figure 12 —A resting egg of the extant branchiopod Eubranchipus vernalis....

Figure 12 —A resting egg of the extant branchiopod Eubranchipus vernalis....

Published: 01 September 2000
Figure 12 —A resting egg of the extant branchiopod Eubranchipus vernalis. Compare its ornamentation with that of Megasphaera ornata n. sp. 1. Entire specimen; 2. close up of envelope ornamentation. The scale bar in 1 represents 100 μm for 1 ; 25 μm for 2. Photos courtesy of Dr. Denton
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Figure 1. Scanning electron micrographs of lobster eggs (A–D) and Neoproter...

Figure 1. Scanning electron micrographs of lobster eggs (A–D) and Neoproter...

in > Geology
Published: 01 January 2003
and filaments of mineralized bacteria. E: Surface of fossil egg envelope ( Megasphaera sp.) exhibiting preservation in fine-grained apatite. F: Cross section of fossilized egg envelope ( Parapandorina raphospissa ) showing coating growing both inward (I) and outward (O). G: Cross section of fossilized egg
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Paleontology of Khesen Formation (northern Mongolia) in thin sections. A: ...

Paleontology of Khesen Formation (northern Mongolia) in thin sections. A: ...

in > Geology
Published: 19 October 2017
, YPM 536800. E: V. gracile showing distal end of processes to upper left, YPM 536802. F: Variomargosphaeridium sp., YPM 536787. G–I: Megasphaera sp. G: YPM 536794. H: YPM 536784. I: YPM 536766. Scale bars 50 μm.
Journal Article

The Weng'an Biota (Doushantuo Formation): an Ediacaran window on soft-bodied and multicellular microorganisms

John A. Cunningham, Kelly Vargas, Zongjun Yin, Stefan Bengtson, Philip C. J. Donoghue
Published: 03 May 2017
Journal of the Geological Society (2017) 174 (5): 793–802.
DOI: https://doi.org/10.1144/jgs2016-142
.... The embryo-like fossils probably represent one taxon dividing from a single cell to thousands of cells ( Fig. 2a–f ). This taxon has been named either Tianzhushania or Megasphaera according to different taxonomic interpretations ( Yin et al. 2004 ; Xiao et al. 2014 b ). Tianzhushania is preferred...
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Experimental mineralization of invertebrate eggs and the preservation of Neoproterozoic embryos

Derek Martin, Derek E.G. Briggs, R. John Parkes
Journal: Geology
Published: 01 January 2003
Geology (2003) 31 (1): 39–42.
DOI: https://doi.org/10.1130/0091-7613(2003)031<0039:EMOIEA>2.0.CO;2
... and filaments of mineralized bacteria. E: Surface of fossil egg envelope ( Megasphaera sp.) exhibiting preservation in fine-grained apatite. F: Cross section of fossilized egg envelope ( Parapandorina raphospissa ) showing coating growing both inward (I) and outward (O). G: Cross section of fossilized egg...
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Possible Algal Origin and Life Cycle of Ediacaran Doushantuo Microfossils with Dextral Spiral Structure

Xi-Guang Zhang, Brian R. Pratt
Published: 01 January 2014
Journal of Paleontology (2014) 88 (1): 92–98.
DOI: https://doi.org/10.1666/13-014
.... In some specimens, the row of holes and rims is replaced by a narrow groove flanked on either side by the rim ( Fig. 1 .2). These spheres are similar in size and external ornamentation to the far more common Megasphaera ornata Xiao and Knoll, 2000 which, however, lacks the helical row of holes...
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