390
Journal of Paleontology 91(3):369–392
Discussion.—Unnamed Form 5 differs from other spherical microfossils by having a single spine-like structure on the surface.
Unnamed Form 6 Figure 11.13
Description.—Microfossil is vase-like in shape, 336 μmin length and 248 μm in width. The neck-like structure is 70 μmin width and 50 μm in length (N = 1).
Discussion.—This specimen has a similar outline to the vase- shaped microfossil Cycliocyrillium torquata, which was repor-
ted from the Neoproterozoic Chuar Group (Porter et al., 2003, figs. 6–15). However, no reinforced margin as that in the vase- shaped microfossils (VSM) has been observed on the new specimen. VSM occur only in the Neoproterozoic. It is not appropriate to claim the relationship between the new specimen and real VSM, since only one specimen has been found in the new microbiota. Therefore, in the interim, it is considered as a new type of potential protist.
Unnamed Form 7 Figure 11.14, 11.15
Description.—Vesicle with short and loosely distributed spine- like ornamentation on the cell surface. Spines do not branch.Cells are 25–101 μmin diameter. Spines are 2–7μm(N = 2) in length.
Discussion.—Only two poorly preserved specimens have been recovered and they have been categorized under undetermined species temporarily.
Acknowledgments
This research project was supported by the National Natural Science Foundation of China (41502008), China Postdoctoral Science Foundation (2015M572221), and the National Basic Research Program of China (2011CB808800). We thank Z. Adam, M. Sharma, and another anonymous reviewer for their critical but inspiring comments on the manuscript. We thank the Editor B. Pratt, Associate Editor N. Butterfield, and Managing Editor S. Marcus for reviewing the manuscript and helping with format. We thank Xin Qian, Guozhen Xu, Tianyu Zhao, and Yan Zhang for their assistance during field works.
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