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Diversity of cnidarians and cycloneuralians in the Fortunian (early Cambrian) Kuanchuanpu Formation at Zhangjiagou, South China

Published online by Cambridge University Press:  15 February 2018

Tiequan Shao ,
Hanhua Tang ,
Yunhuan Liu ,
Dieter Waloszek ,
Andreas Maas  and
Huaqiao Zhang
Tiequan Shao
Affiliation:
School of Earth Science and Resources, Chang’an University, Xi’an 710054, China 〈[email protected]〉, 〈[email protected]〉, 〈[email protected]〉
Hanhua Tang
Affiliation:
School of Earth Science and Resources, Chang’an University, Xi’an 710054, China 〈[email protected]〉, 〈[email protected]〉, 〈[email protected]〉
Yunhuan Liu*
Affiliation:
School of Earth Science and Resources, Chang’an University, Xi’an 710054, China 〈[email protected]〉, 〈[email protected]〉, 〈[email protected]〉
Dieter Waloszek
Affiliation:
University of Lund, Sölvegatan 12, SE-22362 Lund, Sweden 〈[email protected]〉
Andreas Maas
Affiliation:
Galgenackerweg 25, 89134 Blaustein, Germany 〈[email protected]〉
Huaqiao Zhang*
Affiliation:
State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China 〈[email protected]〉
*
*Corresponding authors
*Corresponding authors
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Abstract

The latest discovery of microfossils from the lower Cambrian (Fortunian Stage) Zhangjiagou Lagerstätte in South China are presented. This lagerstätte is rich in exceptionally preserved microfossils, including embryos of Olivooides multisulcatus, Olivooides mirabilis, and Pseudooides prima; hatched stages of O. multisulcatus, O. mirabilis, Hexaconularia sichuanensis, and Quadrapyrgites quadratacris; and cycloneuralians represented by Eopriapulites sphinx. The largest known fragment of O. mirabilis implies that its adult length can be more than 9.0 mm with at least 50 annuli, and the longest known specimen of Q. quadratacris has at least 18 annuli. These unusually large specimens refute the non-feeding larvae hypothesis for Olivooides and Quadrapyrgites.

Based on the current material, it is inferred that (1) early cnidarians have a high diversity in the Fortunian Stage; (2) P. prima might represent the embryonic stages of H. sichuanensis; (3) adults of Olivooides and Quadrapyrgites may have reached centimeter-scale dimensions with more than 50 annuli; (4) Olivooides and Quadrapyrgites may be better interpreted as coronate scyphozoans; (5) cycloneuralians also had a high diversity in the Zhangjiagou Lagerstätte; and (6) cycloneuralians might have originally been part of the early Cambrian meiofauna rather than belonging to the macrobenthos. Such ancestral cycloneuralians might have been Eopriapulites-like, possessing pentaradially symmetric, backward pointing, and internally hollow introvert scalids used as locomotory devices.

Type
Articles
Information
Journal of Paleontology , Volume 92 , Issue 2 , March 2018 , pp. 115 - 129
Copyright
Copyright © 2018, The Paleontological Society 

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